wdiff draft-ietf-ipwave-ipv6-over-80211ocb-08.txt draft-ietf-ipwave-ipv6-over-80211ocb-09.txt

Network Working Group A. Petrescu
Internet-Draft CEA, LIST
Intended status: Standards Track N. Benamar
Expires: March 23, April 9, 2018 Moulay Ismail University
J. Haerri
Eurecom
C. Huitema
Private Octopus Inc.
J. Lee
Sangmyung University
T. Ernst
YoGoKo
T. Li
Peloton Technology
September 19,
October 6, 2017

Transmission of IPv6 Packets over IEEE 802.11 Networks operating in mode
Outside the Context of a Basic Service Set (IPv6-over-80211-OCB)
draft-ietf-ipwave-ipv6-over-80211ocb-08.txt
draft-ietf-ipwave-ipv6-over-80211ocb-09.txt

Abstract

In order to transmit IPv6 packets on IEEE 802.11 networks running
outside the context of a basic service set (OCB, earlier "802.11p")
there is a need to define a few parameters such as the supported
Maximum Transmission Unit size on the 802.11-OCB link, the header
format preceding the IPv6 header, the Type value within it, and
others. This document describes these parameters for IPv6 and IEEE
802.11-OCB networks; it portrays the layering of IPv6 on 802.11-OCB
similarly to other known 802.11 and Ethernet layers - by using an
Ethernet Adaptation Layer.

In addition, the document lists what is different in 802.11-OCB
(802.11p) links compared to more 'traditional' 802.11a/b/g/n links,
where IPv6 protocols operate without issues. Most notably, the
operation outside the context of a BSS (OCB) impacts IPv6 handover
behaviour and IPv6 security.

Status of This Memo

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provisions of BCP 78 and BCP 79.

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This Internet-Draft will expire on March 23, April 9, 2018.

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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6 3
3. Communication Scenarios where IEEE 802.11-OCB Links are Used 7 4
4. Aspects introduced by the OCB mode to 802.11 IPv6 over 802.11-OCB . . . . . . . . 7
5. Layering of IPv6 over 802.11-OCB as over Ethernet . . . . . . 11
5.1. . . . . . . 5
4.1. Maximum Transmission Unit (MTU) . . . . . . . . . . . . . 11
5.2. 5
4.2. Frame Format . . . . . . . . . . . . . . . . . . . . . . 11
5.2.1. 5
4.2.1. Ethernet Adaptation Layer . . . . . . . . . . . . . . 12
5.3. 6
4.3. Link-Local Addresses . . . . . . . . . . . . . . . . . . 14
5.4. 8
4.4. Address Mapping . . . . . . . . . . . . . . . . . . . . . 14
5.4.1. 8
4.4.1. Address Mapping -- Unicast . . . . . . . . . . . . . 14
5.4.2. 8
4.4.2. Address Mapping -- Multicast . . . . . . . . . . . . 15
5.5. 8
4.5. Stateless Autoconfiguration . . . . . . . . . . . . . . . 16
5.6. 8
4.6. Subnet Structure . . . . . . . . . . . . . . . . . . . . 17
6. 9
5. Security Considerations . . . . . . . . . . . . . . . . . . . 17
7. 9
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
8. 10
7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 18
9. 10
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 18
10. 11
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 19
10.1. 11
9.1. Normative References . . . . . . . . . . . . . . . . . . 19
10.2. 11
9.2. Informative References . . . . . . . . . . . . . . . . . 22 14
Appendix A. ChangeLog . . . . . . . . . . . . . . . . . . . . . 23 16
Appendix B. 802.11p . . . . . . . . . . . . . . . . . . . . . . 20
Appendix C. Aspects introduced by the OCB mode to 802.11 . . . . 20
Appendix D. Changes Needed on a software driver 802.11a to
become a 802.11-OCB driver . . . 28 25
Appendix C. E. EPD . . . . . . . . . . . . . . . . . . . . . . . . 26
Appendix F. Design Considerations . . . . . . . . . . . . . . . 29
C.1. 26
F.1. Vehicle ID . . . . . . . . . . . . . . . . . . . . . . . 29
C.2. 27
F.2. Reliability Requirements . . . . . . . . . . . . . . . . 30
C.3. 27
F.3. Multiple interfaces . . . . . . . . . . . . . . . . . . . 30
C.4. 28
F.4. MAC Address Generation . . . . . . . . . . . . . . . . . 31 29

Appendix D. G. IEEE 802.11 Messages Transmitted in OCB mode . . . . 32 29
Appendix E. H. Implementation Status . . . . . . . . . . . . . . . 32
E.1. 29
H.1. Capture in Monitor Mode . . . . . . . . . . . . . . . . . 33
E.2. 30
H.2. Capture in Normal Mode . . . . . . . . . . . . . . . . . 35 33
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 37 35

1. Introduction

This document describes the transmission of IPv6 packets on IEEE Std
802.11-OCB networks [IEEE-802.11-2016] (a.k.a 802.11p) [IEEE-802.11-2016]. "802.11p" see
Appendix B). This involves the layering of IPv6 networking on top of
the IEEE 802.11 MAC layer (with layer, with an LLC layer). layer. Compared to running
IPv6 over the Ethernet MAC layer, there is no modification expected
to IEEE Std 802.11 MAC and Logical Link sublayers: IPv6 works fine
directly over 802.11-OCB too (with too, with an LLC layer).

The term "802.11p" is an earlier definition. layer.

The behaviour of
"802.11p" networks is rolled IPv6 network layer operates on 802.11-OCB in the same manner as
operating on Ethernet, but there are two kinds of exceptions:

o Exceptions due to different operation of IPv6 network layer on
802.11 than on Ethernet. To satisfy these exceptions, this
document IEEE Std 802.11-2016.
In that document the term 802.11p disappears. Instead, each 802.11p
feature is conditioned by the Management Information Base (MIB)
attribute "OCBActivated". Whenever OCBActivated is set to true the
IEEE Std 802.11 OCB state is activated. For example, an 802.11
STAtion operating outside the context of a basic service set has the
OCBActivated flag set. Such a station, when it has the flag set,
uses a BSS identifier equal to ff:ff:ff:ff:ff:ff.

The IPv6 network layer operates on 802.11-OCB in the same manner as
it operates on 802.11 WiFi, with a few particular exceptions. The
IPv6 network layer operates on WiFi by involving describes an Ethernet Adaptation Layer; this Ethernet Adaptation Layer maps 802.11 headers
to between Ethernet II
headers and 802.11 headers. The Ethernet Adaptation Layer is
described Section 4.2.1. The operation of IP on Ethernet is
described in [RFC1042], [RFC2464] and
[I-D.hinden-6man-rfc2464bis]. The
situation of IPv6 networking layer on Ethernet Adaptation Layer is
illustrated below:

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ethernet Adaptation Layer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 WiFi MAC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 WiFi PHY |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

(in

o Exceptions due to the above figure, a WiFi profile is represented; this is used
also for OCB profile.)

A more theoretical and detailed view nature of layer stacking, 802.11-OCB compared to 802.11.
This has impacts on security, privacy, subnet structure and
interfaces between the IP layer
handover behaviour. For security and 802.11-OCB layers, privacy recommendations see
Section 5 and Section 4.5. The subnet structure is illustrated
below. described in
Section 4.6; a new Group ID is requested to be used in such
subnets, see section Section 6. The IP layer operates handover behaviour on top of the EtherType Protocol
Discrimination (EPD); this Discrimination layer OCB
links is not described in IEEE
Std 802.3-2012; this document.

In the interface between IPv6 and EPD is the LLC_SAP
(Link Layer Control Service Access Point).

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 |
+-+-+-+-+-+-{ }+-+-+-+-+-+-+-+
{ LLC_SAP } 802.11-OCB
+-+-+-+-+-+-{ }+-+-+-+-+-+-+-+ Boundary
| EPD | | |
| | MLME | |
+-+-+-{ MAC_SAP }+-+-+-| MLME_SAP |
| MAC Sublayer | | | 802.11-OCB
| and ch. coord. | | SME | Services
+-+-+-{ PHY_SAP }+-+-+-+-+-+-+-| |
| | PLME | |
| PHY Layer | PLME_SAP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

In addition to the description of interface between IP and MAC using
"Ethernet Adaptation Layer" published literature, many documents describe aspects and "Ethernet Protocol Discrimination
(EPD)" it is worth mentioning that SNAP [RFC1042] is used
problems related to carry
the IPv6 Ethertype.

However, there may be some deployment considerations helping optimize
the performances of running IPv6 over 802.11-OCB (e.g. 802.11-OCB:
[I-D.ietf-ipwave-vehicular-networking-survey].

2. Terminology

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in the case of
handovers between 802.11-OCB-enabled access routers, or the
consideration of using the IP security architecture [RFC4301]).

There are currently no specifications for handover between OCB links
since these this
document are currently specified as LLC-1 links (i.e.
connectionless). Any handovers must to be performed above the Data Link
Layer. To realize handovers between OCB links there interpreted as described in RFC 2119 [RFC2119].

WiFi: Wireless Fidelity.

OBRU (On-Board Router Unit): an OBRU is almost always situated in a need for
specific indicators to assist
vehicle; it is a computer with at least two IP interfaces; at least
one IP interface runs in the handover process. The
indicators may OCB mode of 802.11. It MAY be an IP Router.

RSRU (Road-Side Router Advertisements, or 802.11-OCB's Time
Advertisements, or application-layer data. However, this document
does not describe handover behaviour.

The OCB operation is stripped off of all existing 802.11 link-layer
security mechanisms. There Unit): an RSRU is no encryption applied below the
network layer running on 802.11-OCB. At application layer, the IEEE
1609.2 document [IEEE-1609.2] does provide security services for
certain applications to use; application-layer mechanisms are out-of-
scope of this document. On another hand, a security mechanism
provided at networking layer, such as IPsec [RFC4301], may provide
data security protection to almost always situated in a wider range of applications. See
box fixed along the
section Security Considerations road. An RSRU has at least two distinct IP-
enabled interfaces; at least one interface is operated in mode OCB of this document, Section 6

We briefly introduce the vehicular communication scenarios where
IEEE
802.11-OCB links are used. This 802.11 and is followed by IP-enabled. An RSRU is similar to a description of
differences Wireless
Termination Point (WTP), as defined in specification terms, between 802.11-OCB and
802.11a/b/g/n - we answer [RFC5415], or an Access Point
(AP), as defined in IEEE documents, or an Access Network Router (ANR)
defined in [RFC3753], with one key particularity: the question wireless PHY/
MAC layer of what are the aspects
introduced by OCB mode to 802.11; the same aspects, but expressed in
terms at least one of requirements its IP-enabled interfaces is configured
to implementation, are listed operate in Appendix B.) 802.11-OCB mode. The document then concentrates on RSRU communicates with the parameters of layering IP over
802.11-OCB as On
board Unit (OBRU) in the vehicle over Ethernet: value of MTU, 802.11 wireless link operating
in OCB mode. An RSRU MAY be connected to the Frame Format which
includes a description of Internet, and MAY be an Ethernet Adaptation Layer,
IP Router. When it is connected to the forming
of Link-Local Addresses the rules for forming Interface Identifiers
for Stateless Autoconfiguration, the mechanisms for Address Mapping.
These are precisely Internet, the same as IPv6 over Ethernet [RFC2464]. A
reference is made term V2I
(Vehicle to ad-hoc networking characteristics of the subnet
structure in OCB mode.

As an example, these characteristics of layering IPv6 straight over
LLC over 802.11-OCB MAC are illustrated by dissecting an IPv6 packet
captured over a 802.11-OCB link; this Internet) is described relevant.

RSU (Road-Side Unit): an RSU operates in the section
Appendix E.

In the published literature, many documents describe aspects related 802.11-OCB mode. A RSU
broadcasts data to running IPv6 over 802.11-OCB:
[I-D.jeong-ipwave-vehicular-networking-survey].

2. Terminology

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" OBUs or exchanges data with OBUs in this
document are its
communications zone. An RSU may provide channel assignments and
operating instructions to be interpreted as described OBUs in RFC 2119 [RFC2119].

OBRU (On-Board Router Unit): its communications zone, when
required. The basic functional blocks of an OBRU is almost always situated in a
vehicle; it is a RSU are: internal
computer with at least two IP interfaces; at least
one IP processing, permanent storage capability, an integrated GPS
receiver for positioning and timing and an interface runs in that supports
both IPv4 and IPv6 connectivity, compliant with 802.3at. An OCB mode
interface of 802.11. It an RSU MAY be an IP Router.

RSRU (Road-Side Router Unit): an RSRU is almost always situated in a
box fixed along the road. An RSRU has at least two distinct IP-
enabled interfaces; at least one interface is operated in mode OCB of
IEEE 802.11 and is IP-enabled. An RSRU is similar to a Wireless
Termination Point (WTP), as defined in [RFC5415], or an Access Point
(AP), as defined in IEEE documents, or an Access Network Router (ANR)
defined in [RFC3753], with one key particularity: the wireless PHY/
MAC layer of at least one of its IP-enabled interfaces is configured
to operate in 802.11-OCB mode. The RSRU communicates with the On
board Unit (OBRU) in the vehicle over 802.11 wireless link operating
in OCB mode. An RSRU MAY be connected to the Internet, and MAY be an
IP Router. When it is connected to the Internet, the term V2I
(Vehicle to Internet) is relevant.

RSU (Road-Side Unit): an RSU operates in 802.11-OCB mode. A RSU
broadcasts data to OBUs or exchanges data with OBUs in its
communications zone. An RSU may provides channel assignments and
operating instructions to OBUs in its communications zone, when
required. The basic functional blocks of an RSU are: internal
computer processing, permanent storage capability, an integrated GPS
receiver for positioning and timing and an interface that supports
both IPv4 and IPv6 connectivity, compliant with 802.3at. An OCB
interface of an RSU MAY be IP-enabled simultaneously to being WAVE- IP-enabled simultaneously to being WAVE-
enabled or GeoNetworking-enabled (MAY support simultaneously
EtherTypes 0x86DD for IPv6 _and_ 0x88DC for WAVE and 0x8947 for
GeoNetworking).

OCB (outside the context of a basic service set - BSS): A mode of
operation in which a STA is not a member of a BSS and does not
utilize IEEE Std 802.11 authentication, association, or data
confidentiality.

802.11-OCB: mode specified in IEEE Std 802.11-2016 when the MIB
attribute dot11OCBActivited is true. The OCB mode requires
transmission of QoS data frames (IEEE Std 802.11e), half-clocked
operation (IEEE Std 802.11j), and use of 5.9 GHz frequency band.

3. Communication Scenarios where IEEE 802.11-OCB Links are Used

The IEEE 802.11-OCB Networks are used for vehicular communications,
as 'Wireless Access in Vehicular Environments'. The IP communication
scenarios for these environments have been described in several
documents; in particular, we refer the reader to

[I-D.petrescu-its-scenarios-reqs], about scenarios and requirements
for IP in Intelligent Transportation Systems.

The link model is the following: STA --- 802.11-OCB --- STA. In
vehicular networks, STAs can be RSRUs and/or OBRUs. While 802.11-OCB
is clearly specified, and the use of IPv6 over such link is not
radically new, the operating environment (vehicular networks) brings
in new perspectives.

The 802.11-OCB links form and terminate; nodes connected to these
links peer, and discover each other; the nodes are mobile. However,
the precise description of how links discover each other, peer and
manage mobility is not given in this document.

4. Aspects introduced by the OCB mode to 802.11

In the IEEE IPv6 over 802.11-OCB mode, all nodes

4.1. Maximum Transmission Unit (MTU)

The default MTU for IP packets on 802.11-OCB is 1500 octets. It is
the same value as IPv6 packets on Ethernet links, as specified in
[RFC2464]. This value of the wireless range can
directly communicate with each other without involving authentication
or association procedures. At link layer, it is necessary to set MTU respects the
same channel number (or frequency) on two stations recommendation that need to
communicate with each other. Stations STA1
every link on the Internet must have a minimum MTU of 1280 octets
(stated in [RFC8200], and STA2 can exchange IP the recommendations therein, especially
with respect to fragmentation). If IPv6 packets if they of size larger than
1500 bytes are set sent on an 802.11-OCB interface card then the same channel. At IP layer, they then
discover each other by using stack
will fragment. In case there are IP fragments, the IPv6 Neighbor Discovery protocol.

Briefly, field "Sequence
number" of the IEEE 802.11-OCB mode has 802.11 Data header containing the following properties:

o The use by each node IP fragment field is
increased.

Non-IP packets such as WAVE Short Message Protocol (WSMP) can be
delivered on 802.11-OCB links. Specifications of a 'wildcard' BSSID (i.e., each bit these packets are
out of scope of this document, and do not impose any limit on the
BSSID MTU
size, allowing an arbitrary number of 'containers'. Non-IP packets
such as ETSI GeoNetworking packets have an MTU of 1492 bytes. The
operation of IPv6 over GeoNetworking is set to 1)

o No IEEE 802.11 Beacon frames specified at
[ETSI-IPv6-GeoNetworking].

4.2. Frame Format

IP packets are transmitted

o No authentication over 802.11-OCB as standard Ethernet
packets. As with all 802.11 frames, an Ethernet adaptation layer is required in order to be able to communicate

o No association
used with 802.11-OCB as well. This Ethernet Adaptation Layer
performing 802.11-to-Ethernet is needed described in order to be able to communicate

o No encryption Section 4.2.1. The
Ethernet Type code (EtherType) for IPv6 is provided in order to be able to communicate

o Flag dot11OCBActivated 0x86DD (hexadecimal 86DD,
or otherwise #86DD).

The Frame format for transmitting IPv6 on 802.11-OCB networks is set to true

All the nodes
same as transmitting IPv6 on Ethernet networks, and is described in
section 3 of [RFC2464].

1 0 0 0 0 1 1 0 1 1 0 1 1 1 0 1
is the radio communication range (OBRU binary representation of the EtherType value 0x86DD.

4.2.1. Ethernet Adaptation Layer

An 'adaptation' layer is inserted between a MAC layer and RSRU)
receive all the messages transmitted (OBRU
Networking layer. This is used to transform some parameters between
their form expected by the IP stack and RSRU) within the radio
communications range. The eventual conflict(s) are resolved form provided by the MAC CDMA function.

The following message exchange diagram illustrates a comparison
between traditional 802.11 and
layer.

An Ethernet Adaptation Layer makes an 802.11 in OCB mode. The 'Data'
messages can be MAC look to IP packets such
Networking layer as HTTP or others. Other 802.11
management and control frames (non IP) may be transmitted, a more traditional Ethernet layer. At reception,
this layer takes as
specified in input the IEEE 802.11 standard. For information, Data Header and the names of
these messages as currently specified by
Logical-Link Layer Control Header and produces an Ethernet II Header.
At sending, the 802.11 standard are
listed in Appendix D.

STA AP STA1 STA2
| | | reverse operation is performed.

+--------------------+------------+-------------+---------+-----------+
|
|<------ Beacon -------| |<------ 802.11 Data -------->|
| Header | LLC Header | IPv6 Header |
|---- Probe Req. ----->| |<------ Data -------->|
|<--- Probe Res. ------| | |
| | |<------ Data -------->|
|---- Auth Req. ------>| | |
|<--- Auth Res. -------| |<------ Data -------->|
| | | |
|---- Asso Req. ------>| |<------ Data -------->|
|<--- Asso Res. -------| Payload |.11 Trailer|
+--------------------+------------+-------------+---------+-----------+
\ / \ /
----------------------------- --------
\---------------------------------------------/
^
|
802.11-to-Ethernet Adaptation Layer
|
v
+---------------------+-------------+---------+
| Ethernet II Header | |<------ Data -------->|
|<------ Data -------->| IPv6 Header | Payload |
|<------ Data -------->| |<------ Data -------->|

(a) 802.11 Infrastructure mode (b) 802.11-OCB mode
+---------------------+-------------+---------+

The interface 802.11-OCB was specified Receiver and Transmitter Address fields in IEEE Std 802.11p (TM) -2010
[IEEE-802.11p-2010] as an amendment to IEEE Std the 802.11 (TM) -2007,
titled "Amendment 6: Wireless Access Data Header
contain the same values as the Destination and the Source Address
fields in Vehicular Environments".
Since then, this amendment has been included the Ethernet II Header, respectively. The value of the
Type field in IEEE 802.11(TM) -2012
and -2016 [IEEE-802.11-2016].

In document 802.11-2016, anything qualified specifically the LLC Header is the same as
"OCBActivated", or "outside the context value of a basic service" set to be
true, then it is actually referring to OCB aspects introduced to
802.11.

In order to delineate the aspects introduced by 802.11-OCB to 802.11,
we refer to Type
field in the earlier [IEEE-802.11p-2010]. Ethernet II Header.

The amendment is
concerned with vehicular communications, where ".11 Trailer" contains solely a 4-byte Frame Check Sequence.

Additionally, the wireless link is
similar Ethernet Adaptation Layer performs operations in
relation to that IP fragmentation and MTU. One of Wireless LAN (using a PHY layer specified by
802.11a/b/g/n), but which needs to cope with the high mobility factor
inherent in scenarios of communications between moving vehicles, and
between vehicles and fixed infrastructure deployed along roads.
While 'p' is a letter just like 'a, b, g' and 'n' are, 'p' is
concerned more with MAC modifications, and a little with PHY
modifications; the others are mainly about PHY modifications. It these operations is
possible
briefly described in practice to combine a 'p' MAC with an 'a' PHY by
operating outside the context of a BSS with OFDM at 5.4GHz and
5.9GHz.

The 802.11-OCB links are specified to section Section 4.1.

In OCB mode, IPv6 packets MAY be compatible transmitted either as much "IEEE 802.11
Data" or alternatively as
possible with the behaviour of 802.11a/b/g/n and future generation
IEEE WLAN links. From the IP perspective, an 802.11-OCB MAC layer
offers practically the same interface to IP "IEEE 802.11 QoS Data", as illustrated in
the WiFi and Ethernet
layers do (802.11a/b/g/n and 802.3). A packet sent by an OBRU may be
received by one figure below.

or multiple RSRUs.

The link-layer resolution distinction between the two formats is
performed given by using the IPv6 Neighbor Discovery protocol.

To support this similarity statement (IPv6 is layered on top value of LLC
on top the
field "Type/Subtype". The value of 802.11-OCB, the field "Type/Subtype" in the same way that IPv6
802.11 Data header is layered on top of
LLC on top 0x0020. The value of 802.11a/b/g/n (for WLAN) or layered on top of LLC on
top of 802.3 (for Ethernet)) it is useful to analyze the differences
between 802.11-OCB and field "Type/Subtype"
in the 802.11 specifications. During this analysis,
we note that whereas 802.11-OCB lists relatively complex and numerous
changes to QoS header is 0x0028.

The mapping between qos-related fields in the MAC layer (and very little to IPv6 header (e.g.
"Traffic Class", "Flow label") and fields in the PHY layer), there "802.11 QoS Data
Header" (e.g. "QoS Control") are only a few characteristics which may be important not specified in this document.
Guidance for an
implementation transmitting IPv6 packets on 802.11-OCB links. a potential mapping is provided in
[I-D.ietf-tsvwg-ieee-802-11], although it is not specific to OCB
mode.

The most important 802.11-OCB point which influences the placement of IPv6
functioning networking layer on Ethernet Adaptation Layer
is illustrated below:

(in the OCB characteristic; an additional, less direct
influence, above figure, a WiFi profile is the maximum bandwidth afforded by the PHY modulation/
demodulation methods represented; this is used
also for OCB profile.)

Other alternative views of layering are EtherType Protocol
Discrimination (EPD), see Appendix E, and channel access specified by 802.11-OCB. SNAP see [RFC1042].

4.3. Link-Local Addresses

The
maximum bandwidth theoretically possible in link-local address of an 802.11-OCB interface is 54 Mbit/s
(when using, for example, formed in the following parameters: 20 MHz channel;
modulation 64-QAM; codint rate R
same manner as on an Ethernet interface. This manner is 3/4); described in practice
section 5 of IP-over-
802.11-OCB a commonly observed figure is 12Mbit/s; this bandwidth
allows [RFC2464]. Additionally, if stable identifiers are
needed, it is recommended to follow the operation of a wide range of protocols relying Recommendation on IPv6.

o Operation Outside the Context of a BSS (OCB): the (earlier
802.11p) 802.11-OCB links Stable IPv6
Interface Identifiers [RFC8064]. Additionally, if semantically
opaque Interface Identifiers are operated without needed, a Basic Service Set
(BSS). This means that potential method for
generating semantically opaque Interface Identifiers with IPv6
Stateless Address Autoconfiguration is given in [RFC7217].

4.4. Address Mapping

For unicast as for multicast, there is no change from the frames IEEE 802.11 Beacon, Association
Request/Response, Authentication Request/Response, unicast and similar,
are not used. The used identifier of BSS (BSSID) has a
hexadecimal value always 0xffffffffffff (48 '1' bits, represented
as MAC
multicast address ff:ff:ff:ff:ff:ff, or otherwise the 'wildcard'
BSSID), mapping format of Ethernet interfaces, as opposed to an arbitrary BSSID value set defined
by
administrator (e.g. 'My-Home-AccessPoint'). The OCB operation -
namely the lack of beacon-based scanning sections 6 and lack 7 of
authentication - should be taken into account when the Mobile IPv6
protocol [RFC6275] and the protocols [RFC2464].

4.4.1. Address Mapping -- Unicast

The procedure for IP mapping IPv6 unicast addresses into Ethernet link-
layer security

[RFC4301] are used. The way these protocols adapt to OCB addresses is not described in this document.

o Timing Advertisement: is a new message defined in 802.11-OCB,
which does not exist in 802.11a/b/g/n. This message is used by
stations to inform other stations about the value [RFC4861].

4.4.2. Address Mapping -- Multicast

A Group ID named TBD, of time. It length 112bits is
similar requested to IANA; this
Group ID signifies "All 80211OCB Interfaces Address". Only the time as delivered by a GNSS system (Galileo, GPS,
...) or by a cellular system. This message is optional for
implementation.

o Frequency range: least
32 significant bits of this is "All 80211OCB Interfaces Address" will be
mapped to and from a characteristic of the PHY layer, with
almost no impact on MAC multicast address.

Transmitting IPv6 packets to multicast destinations over 802.11 links
proved to have some performance issues
[I-D.perkins-intarea-multicast-ieee802]. These issues may be
exacerbated in OCB mode. Solutions for these problems should
consider the OCB mode of operation.

4.5. Stateless Autoconfiguration

The Interface Identifier for an 802.11-OCB interface between MAC and IP. However, it is worth considering that formed using
the frequency range is regulated by a
regional authority (ARCEP, ETSI, FCC, etc.); same rules as part of the
regulation process, specific applications are associated with
specific frequency ranges. In the case of 802.11-OCB, the
regulator associates a set Interface Identifier for an Ethernet interface;
this is described in section 4 of frequency ranges, or slots within a
band, to [RFC2464]. No changes are needed,
but some care must be taken when considering the use of applications of vehicular communications, in a
band known as "5.9GHz". the Stateless
Address Auto-Configuration procedure.

The 5.9GHz band is different from bits in the
2.4GHz interface identifier have no generic meaning and 5GHz bands used by Wireless LAN. However, the
identifier should be treated as with
Wireless LAN, an opaque value. The bits
'Universal' and 'Group' in the operation identifier of an 802.11-OCB in "5.9GHz" bands interface
are significant, as this is
exempt from owning a license an IEEE link-layer address. The details
of this significance are described in EU (in US [RFC7136].

As with all Ethernet and 802.11 interface identifiers ([RFC7721]),
the 5.9GHz is a licensed
band identifier of spectrum; for the fixed infrastructure an explicit FCC
autorization is required; for an onboard device a 'licensed-by-
rule' concept applies: rule certification conformity is required);
however technical conditions are different than those of the bands
"2.4GHz" or "5GHz". On one hand, the allowed power levels, 802.11-OCB interface may involve privacy, MAC
address spoofing and
implicitly the maximum allowed distance between vehicles, IP address hijacking risks. A vehicle embarking
an On-Board Unit whose egress interface is of
33dBm for 802.11-OCB (in Europe), compared to 20 dBm for Wireless
LAN 802.11a/b/g/n; this leads to a maximum distance of
approximately 1km, compared to approximately 50m. On the other
hand, specific conditions related may expose
itself to congestion avoidance, jamming
avoidance, eavesdropping and radar detection are imposed on the use subsequent correlation of DSRC (in
US) and on data; this may
reveal data considered private by the use vehicle owner; there is a risk
of frequencies for Intelligent Transportation
Systems (in EU), compared to Wireless LAN (802.11a/b/g/n).

o 'Half-rate' encoding: as being tracked; see the frequency range, this parameter is
related privacy considerations described in
Appendix F.

If stable Interface Identifiers are needed in order to PHY, and thus has not much impact form IPv6
addresses on the interface
between the IP layer and the MAC layer.

o In vehicular communications using 802.11-OCB links, there are
strong privacy requirements with respect it is recommended to addressing. While follow the
802.11-OCB standard does not specify anything in particular with
respect to MAC addresses,
recommendation in these settings there exists a strong
need [RFC8064]. Additionally, if semantically opaque
Interface Identifiers are needed, a potential method for dynamic change of these addresses (as opposed to the non-
vehicular settings - real wall protection - where fixed MAC
addresses do not currently pose some privacy risks). This generating
semantically opaque Interface Identifiers with IPv6 Stateless Address
Autoconfiguration is
further described given in section Section 6. [RFC7217].

4.6. Subnet Structure

A relevant function subnet is
described in IEEE 1609.3-2016 [IEEE-1609.3], clause 5.5.1 and IEEE
1609.4-2016 [IEEE-1609.4], clause 6.7.

Other aspects particular to 802.11-OCB, which are also particular to
802.11 (e.g. the 'hidden node' operation), may have an influence on formed by the use of transmission of IPv6 packets on external 802.11-OCB networks. The
OCB interfaces of vehicles
that are in close range (not their on-board interfaces). This
ephemeral subnet structure is described in section Section 5.6.

5. Layering strongly influenced by the mobility of IPv6 over 802.11-OCB
vehicles: the 802.11 hidden node effects appear. On another hand,
the structure of the internal subnets in each car is relatively
stable.

The 802.11 networks in OCB mode may be considered as over Ethernet

5.1. Maximum Transmission Unit (MTU) 'ad-hoc'
networks. The default MTU addressing model for IP packets on 802.11-OCB is 1500 octets. It such networks is
the same value as IPv6 packets on Ethernet links, as specified described in
[RFC2464]. This value
[RFC5889].

An addressing model involves several types of the MTU respects the recommendation that
every link addresses, like
Globally-unique Addresses (GUA), Link-Local Addresses (LL) and Unique
Local Addresses (ULA). The subnet structure in the Internet must 'ad-hoc' networks may
have a minimum MTU characteristics that lead to difficulty of 1280 octets
(stated in [RFC8200], and using GUAs derived
from a received prefix, but the recommendations therein, especially
with respect LL addresses may be easier to fragmentation). If IPv6 packets of size larger than
1500 bytes are sent on an 802.11-OCB interface card then the IP stack
will fragment. In case there are IP fragments, the field "Sequence
number" of use
since the 802.11 Data header containing prefix is constant.

5. Security Considerations

Any security mechanism at the IP fragment field is
increased.

Non-IP packets such as WAVE Short Message Protocol (WSMP) can layer or above that may be
delivered on 802.11-OCB links. Specifications of these packets are carried
out of scope of this document, and do not impose any limit on for the MTU
size, allowing an arbitrary number of 'containers'. Non-IP packets
such as ETSI GeoNetworking packets have an MTU of 1492 bytes. The
operation general case of IPv6 may also be carried out for IPv6
operating over GeoNetworking 802.11-OCB.

The OCB operation is specified at
[ETSI-IPv6-GeoNetworking].

5.2. Frame Format

IP packets are transmitted over 802.11-OCB as standard Ethernet
packets. As with stripped off of all existing 802.11 frames, an Ethernet adaptation layer is
used with 802.11-OCB as well. This Ethernet Adaptation Layer
performing 802.11-to-Ethernet is described in Section 5.2.1. The
Ethernet Type code (EtherType) for IPv6 is 0x86DD (hexadecimal 86DD,
or otherwise #86DD).

The Frame format for transmitting IPv6 on 802.11-OCB networks link-layer
security mechanisms. There is no encryption applied below the
same as transmitting IPv6
network layer running on Ethernet networks, and is described in
section 3 of [RFC2464]. The frame format 802.11-OCB. At application layer, the IEEE
1609.2 document [IEEE-1609.2] does provide security services for transmitting IPv6
packets over Ethernet is illustrated below:

0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Destination |
+- -+
| Ethernet |
+- -+
| Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source |
+- -+
| Ethernet |
+- -+
| Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1 0 0 0 0 1 1 0 1 1 0 1 1 1 0 1|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 |
+- -+
| header |
+- -+
| and |
+- -+
/ payload ... /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
(Each tic mark represents one bit.)

Ethernet II Fields:

Destination Ethernet Address
the MAC destination address.

Source Ethernet Address
certain applications to use; application-layer mechanisms are out-of-
scope of this document. On another hand, a security mechanism
provided at networking layer, such as IPsec [RFC4301], may provide
data security protection to a wider range of applications.

802.11-OCB does not provide any cryptographic protection, because it
operates outside the MAC source address.

1 0 0 0 0 1 1 0 1 1 0 1 1 1 0 1
binary representation context of a BSS (no Association Request/
Response, no Challenge messages). Any attacker can therefore just
sit in the EtherType value 0x86DD.

IPv6 header and payload near range of vehicles, sniff the IPv6 packet containing IPv6 header and payload.

5.2.1. Ethernet Adaptation Layer

In general, an 'adaptation' layer is inserted between a MAC layer and network (just set the Networking layer. This is used
interface card's frequency to transform some parameters
between their form expected by the IP stack proper range) and the form provided by
the MAC layer. For example, an 802.15.4 adaptation layer may perform
fragmentation and reassembly operations on attacks
without needing to physically break any wall. Such a MAC whose maximum Packet
Data Unit size link is smaller less
protected than the minimum MTU recognized by the IPv6
Networking layer. Other examples involve link-layer address
transformation, packet header insertion/removal, and so on.

An Ethernet Adaptation Layer makes an 802.11 commonly used links (wired link or protected 802.11).

The potential attack vectors are: MAC look to address spoofing, IP
Networking layer as a more traditional Ethernet layer. At reception,
this layer takes as input the IEEE 802.11 Data Header address
and session hijacking and privacy violation.

Within the
Logical-Link Layer Control Header IPsec Security Architecture [RFC4301], the IPsec AH and produces an Ethernet II Header.
At sending,
ESP headers [RFC4302] and [RFC4303] respectively, its multicast
extensions [RFC5374], HTTPS [RFC2818] and SeND [RFC3971] protocols
can be used to protect communications. Further, the reverse operation assistance of
proper Public Key Infrastructure (PKI) protocols [RFC4210] is performed.

The Receiver and Transmitter Address fields
necessary to establish credentials. More IETF protocols are
available in the 802.11 Data Header
contain the same values as toolbox of the Destination IP security protocol designer.
Certain ETSI protocols related to security protocols in Intelligent
Transportation Systems are described in [ETSI-sec-archi].

As with all Ethernet and the Source Address
fields 802.11 interface identifiers, there may
exist privacy risks in the Ethernet II Header, respectively. The value use of the
Type field 802.11-OCB interface identifiers.
Moreover, in outdoors vehicular settings, the LLC Header is the same as the value of the Type
field privacy risks are more
important than in indoors settings. New risks are induced by the Ethernet II Header.

The ".11 Trailer" contains solely a 4-byte Frame Check Sequence.

The Ethernet Adaptation Layer performs operations in relation to
possibility of attacker sniffers deployed along routes which listen
for IP
fragmentation and MTU. One packets of these operations vehicles passing by. For this reason, in the
802.11-OCB deployments, there is briefly described a strong necessity to use protection
tools such as dynamically changing MAC addresses. This may help
mitigate privacy risks to a certain level. On another hand, it may
have an impact in section Section 5.1.

In OCB mode, the way typical IPv6 packets can be transmitted either as "IEEE 802.11
Data" or alternatively as "IEEE 802.11 QoS Data", as illustrated address auto-configuration is
performed for vehicles (SLAAC would rely on MAC addresses amd would
hence dynamically change the affected IP address), in the figure below. Some commercial OCB products use 802.11 Data, and
others 802.11 QoS data. In way the future, both could be used.

+--------------------+-------------+-------------+---------+-----------+
| 802.11 QoS Data Hdr| LLC Header | Privacy addresses were used, and other effects.

6. IANA Considerations

A Group ID named TBD, of length 112bits is requested to IANA; this
Group ID signifies "All 80211OCB Interfaces Address".

7. Contributors

Christian Huitema, Tony Li.

Romain Kuntz contributed extensively about IPv6 Header | Payload |.11 Trailer|
+--------------------+-------------+-------------+---------+-----------+

The distinction handovers between
links running outside the two formats is given by context of a BSS (802.11-OCB links).

Tim Leinmueller contributed the value idea of the
field "Type/Subtype". The value use of IPv6 over
802.11-OCB for distribution of certificates.

Marios Makassikis, Jose Santa Lozano, Albin Severinson and Alexey
Voronov provided significant feedback on the field "Type/Subtype" experience of using IP
messages over 802.11-OCB in initial trials.

Michelle Wetterwald contributed extensively the
802.11 Data header is 0x0020. The value of MTU discussion,
offered the field "Type/Subtype"
in ETSI ITS perspective, and reviewed other parts of the 802.11 QoS header is 0x0028.
document.

8. Acknowledgements

The mapping between qos-related fields in the IPv6 header (e.g.
"Traffic Class", "Flow label") authors would like to thank Witold Klaudel, Ryuji Wakikawa,
Emmanuel Baccelli, John Kenney, John Moring, Francois Simon, Dan
Romascanu, Konstantin Khait, Ralph Droms, Richard 'Dick' Roy, Ray
Hunter, Tom Kurihara, Michal Sojka, Jan de Jongh, Suresh Krishnan,
Dino Farinacci, Vincent Park, Jaehoon Paul Jeong, Gloria Gwynne,
Hans-Joachim Fischer, Russ Housley, Rex Buddenberg, Erik Nordmark,
Bob Moskowitz, Andrew (Dryden?), Georg Mayer, Dorothy Stanley, Sandra
Cespedes, Mariano Falcitelli, Sri Gundavelli, Abdussalam Baryun,
Margaret Cullen and fields in William Whyte. Their valuable comments clarified
particular issues and generally helped to improve the "802.11 QoS Data
Header" (e.g. "QoS Control") are not specified in this document.
Guidance

Pierre Pfister, Rostislav Lisovy, and others, wrote 802.11-OCB
drivers for a potential mapping is provided in
[I-D.ietf-tsvwg-ieee-802-11], although it is not specific linux and described how.

For the multicast discussion, the authors would like to OCB
mode.

5.3. Link-Local Addresses

The link-local address of an 802.11-OCB interface is formed thank Owen
DeLong, Joe Touch, Jen Linkova, Erik Kline, Brian Haberman and
participants to discussions in network working groups.

The authours would like to thank participants to the
same manner as on an Ethernet interface. This manner is described Birds-of-
a-Feather "Intelligent Transportation Systems" meetings held at IETF
in
section 5 of [RFC2464]. Additionally, if stable identifiers are
needed, it is recommended 2016.

9. References

9.1. Normative References

[I-D.ietf-tsvwg-ieee-802-11]
Szigeti, T., Henry, J., and F. Baker, "Diffserv to follow the Recommendation on Stable IPv6
Interface Identifiers [RFC8064]. Additionally, if semantically
opaque Interface Identifiers are needed, a potential method for
generating semantically opaque Interface Identifiers with IPv6
Stateless Address Autoconfiguration is given IEEE
802.11 Mapping", draft-ietf-tsvwg-ieee-802-11-09 (work in [RFC7217].

5.4. Address Mapping

For unicast as for multicast, there is no change from the unicast and
multicast address mapping format of Ethernet interfaces, as defined
by sections 6
progress), September 2017.

[RFC1042] Postel, J. and 7 of [RFC2464].

5.4.1. Address Mapping -- Unicast

The procedure J. Reynolds, "Standard for mapping IPv6 unicast addresses into Ethernet link-
layer addresses is described in [RFC4861]. The Source/Target Link-
layer Address option has the following form when the link-layer is
Ethernet.

0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+- Ethernet -+
| |
+- Address -+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Option fields:

Type
1 for Source Link-layer address.
2 for Target Link-layer address.

Length
1 (in units transmission
of 8 octets).

Ethernet Address
The 48 bit Ethernet IP datagrams over IEEE 802 address, in canonical bit order.

5.4.2. Address Mapping -- Multicast

IPv6 protocols often make networks", STD 43, RFC 1042,
DOI 10.17487/RFC1042, February 1988,
<https://www.rfc-editor.org/info/rfc1042>.

[RFC2119] Bradner, S., "Key words for use of IPv6 multicast addresses in the
destination field of IPv6 headers. For example, an ICMPv6 link-
scoped Neighbor Advertisement is sent RFCs to the IPv6 address ff02::1
denoted "all-nodes" address. When transmitting these packets on
802.11-OCB links it is necessary to map the IPv6 address to a MAC
address.

The same mapping requirement applies to the link-scoped multicast
addresses of other IPv6 protocols as well. In DHCPv6, the
"All_DHCP_Servers" IPv6 multicast address ff02::1:2, and in OSPF the
"All_SPF_Routers" IPv6 multicast address ff02::5, need to be mapped
on a multicast MAC address.

An IPv6 packet with a multicast destination address DST, consisting
of the sixteen octets DST[1] through DST[16], is transmitted to the
IEEE 802.11-OCB MAC multicast address whose first two octets are the
value 0x3333 and whose last four octets are the last four octets of
DST.

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 1 1 0 0 1 1|0 0 1 1 0 0 1 1|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DST[13] | DST[14] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DST[15] | DST[16] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

A Group ID named TBD, of length 112bits is requested to IANA; this
Group ID signifies "All 80211OCB Interfaces Address". Only the least
32 significant bits Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.

[RFC2464] Crawford, M., "Transmission of this "All 80211OCB Interfaces Address" will be
mapped to and from a MAC multicast address.

Transmitting IPv6 packets to multicast destinations Packets over 802.11 links
proved to have some performance issues
[I-D.perkins-intarea-multicast-ieee802]. These issues may be
exacerbated in OCB mode. Solutions for these problems should
consider the OCB mode of operation.

5.5. Stateless Autoconfiguration

The Interface Identifier for an 802.11-OCB interface is formed using
the same rules as the Interface Identifier for an Ethernet interface;
this is described in section 4 of [RFC2464]. No changes are needed,
but some care must be taken when considering the use of the SLAAC
procedure.

The bits in the the interface identifier have no generic meaning and
the identifier should be treated as an opaque value. The bits
'Universal' and 'Group' in the identifier of an 802.11-OCB interface
are significant, as this is an IEEE link-layer address. The details
of this significance are described in [RFC7136].

As with all Ethernet and 802.11 interface identifiers ([RFC7721]),
the identifier of an 802.11-OCB interface may involve privacy, MAC
address spoofing and IP address hijacking risks. A vehicle embarking
an On-Board Unit whose egress interface is 802.11-OCB may expose
itself to eavesdropping and subsequent correlation of data; this may
reveal data considered private by the vehicle owner; there is a risk
of being tracked; see the privacy considerations described in
Appendix C.

If stable Interface Identifiers are needed in order to form IPv6
addresses on 802.11-OCB links, it is recommended to follow the
recommendation in [RFC8064]. Additionally, if semantically opaque
Interface Identifiers are needed, a potential method for generating
semantically opaque Interface Identifiers with IPv6 Stateless Address
Autoconfiguration is given in [RFC7217].

5.6. Subnet Structure

A subnet is formed by the external 802.11-OCB interfaces of vehicles
that are in close range (not their on-board interfaces). This
ephemeral subnet structure is strongly influenced by the mobility of
vehicles: the 802.11 hidden node effects appear. On another hand,
the structure of the internal subnets in each car is relatively
stable.

For routing purposes, a prefix exchange mechanism could be needed
between neighboring vehicles.

The 802.11 networks in OCB mode may be considered as 'ad-hoc'
networks. The addressing model for such networks is described in
[RFC5889].

An addressing model involves several types of addresses, like
Globally-unique Addresses (GUA), Link-Local Addresses (LL)
Networks", RFC 2464, DOI 10.17487/RFC2464, December 1998,
<https://www.rfc-editor.org/info/rfc2464>.

[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
DOI 10.17487/RFC2818, May 2000,
<https://www.rfc-editor.org/info/rfc2818>.

[RFC3753] Manner, J., Ed. and Unique
Local Addresses (ULA). The subnet structure in 'ad-hoc' networks may
have characteristics that lead to difficulty of using GUAs derived
from a received prefix, but the LL addresses may be easier to use
since the prefix is constant.

6. Security Considerations

Any security mechanism at the IP layer or above that may be carried
out M. Kojo, Ed., "Mobility Related
Terminology", RFC 3753, DOI 10.17487/RFC3753, June 2004,
<https://www.rfc-editor.org/info/rfc3753>.

[RFC3971] Arkko, J., Ed., Kempf, J., Zill, B., and P. Nikander,
"SEcure Neighbor Discovery (SEND)", RFC 3971,
DOI 10.17487/RFC3971, March 2005,
<https://www.rfc-editor.org/info/rfc3971>.

[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for the general case of IPv6 may also be carried out Security", BCP 106, RFC 4086,
DOI 10.17487/RFC4086, June 2005,
<https://www.rfc-editor.org/info/rfc4086>.

[RFC4210] Adams, C., Farrell, S., Kause, T., and T. Mononen,
"Internet X.509 Public Key Infrastructure Certificate
Management Protocol (CMP)", RFC 4210,
DOI 10.17487/RFC4210, September 2005,
<https://www.rfc-editor.org/info/rfc4210>.

[RFC4301] Kent, S. and K. Seo, "Security Architecture for IPv6
operating over 802.11-OCB.

802.11-OCB does not provide any cryptographic protection, because it
operates outside the context of a BSS (no Association Request/
Response, no Challenge messages). Any attacker can therefore just
sit in the near range of vehicles, sniff the network (just set the
interface card's frequency to the proper range)
Internet Protocol", RFC 4301, DOI 10.17487/RFC4301,
December 2005, <https://www.rfc-editor.org/info/rfc4301>.

[RFC4302] Kent, S., "IP Authentication Header", RFC 4302,
DOI 10.17487/RFC4302, December 2005,
<https://www.rfc-editor.org/info/rfc4302>.

[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, DOI 10.17487/RFC4303, December 2005,
<https://www.rfc-editor.org/info/rfc4303>.

[RFC4861] Narten, T., Nordmark, E., Simpson, W., and perform attacks
without needing to physically break any wall. Such a link is less
protected than commonly used links (wired link or protected 802.11).

The potential attack vectors are: MAC address spoofing, H. Soliman,
"Neighbor Discovery for IP address
and session hijacking version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.

[RFC5374] Weis, B., Gross, G., and privacy violation.

Within D. Ignjatic, "Multicast
Extensions to the IPsec Security Architecture [RFC4301], for the IPsec AH Internet
Protocol", RFC 5374, DOI 10.17487/RFC5374, November 2008,
<https://www.rfc-editor.org/info/rfc5374>.

[RFC5415] Calhoun, P., Ed., Montemurro, M., Ed., and
ESP headers [RFC4302] D. Stanley,
Ed., "Control And Provisioning of Wireless Access Points
(CAPWAP) Protocol Specification", RFC 5415,
DOI 10.17487/RFC5415, March 2009,
<https://www.rfc-editor.org/info/rfc5415>.

[RFC5889] Baccelli, E., Ed. and [RFC4303] respectively, its multicast
extensions [RFC5374], HTTPS [RFC2818] M. Townsley, Ed., "IP Addressing
Model in Ad Hoc Networks", RFC 5889, DOI 10.17487/RFC5889,
September 2010, <https://www.rfc-editor.org/info/rfc5889>.

[RFC6275] Perkins, C., Ed., Johnson, D., and SeND [RFC3971] protocols
can be used to protect communications. Further, the assistance of
proper Public Key Infrastructure (PKI) protocols [RFC4210] is
necessary to establish credentials. More IETF protocols are
available J. Arkko, "Mobility
Support in the toolbox IPv6", RFC 6275, DOI 10.17487/RFC6275, July
2011, <https://www.rfc-editor.org/info/rfc6275>.

[RFC7136] Carpenter, B. and S. Jiang, "Significance of IPv6
Interface Identifiers", RFC 7136, DOI 10.17487/RFC7136,
February 2014, <https://www.rfc-editor.org/info/rfc7136>.

[RFC7217] Gont, F., "A Method for Generating Semantically Opaque
Interface Identifiers with IPv6 Stateless Address
Autoconfiguration (SLAAC)", RFC 7217,
DOI 10.17487/RFC7217, April 2014,
<https://www.rfc-editor.org/info/rfc7217>.

[RFC7721] Cooper, A., Gont, F., and D. Thaler, "Security and Privacy
Considerations for IPv6 Address Generation Mechanisms",
RFC 7721, DOI 10.17487/RFC7721, March 2016,
<https://www.rfc-editor.org/info/rfc7721>.

[RFC8064] Gont, F., Cooper, A., Thaler, D., and W. Liu,
"Recommendation on Stable IPv6 Interface Identifiers",
RFC 8064, DOI 10.17487/RFC8064, February 2017,
<https://www.rfc-editor.org/info/rfc8064>.

[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.

9.2. Informative References

[ETSI-IPv6-GeoNetworking]
"ETSI EN 302 636-6-1 v1.2.1 (2014-05), ETSI, European
Standard, Intelligent Transportation Systems (ITS);
Vehicular Communications; Geonetworking; Part 6: Internet
Integration; Sub-part 1: Transmission of the IP security protocol designer.
Certain IPv6 Packets over
Geonetworking Protocols. Downloaded on September 9th,
2017, freely available from ETSI protocols related to website at URL
http://www.etsi.org/deliver/
etsi_en/302600_302699/30263601/01.02.01_60/
en_30263601v010201p.pdf".

[ETSI-sec-archi]
"ETSI TS 102 940 V1.2.1 (2016-11), ETSI Technical
Specification, Intelligent Transport Systems (ITS);
Security; ITS communications security protocols architecture and
security management, November 2016. Dowloaded on
September 9th, 2017, freely available from ETSI website at
URL http://www.etsi.org/deliver/
etsi_ts/102900_102999/102940/01.02.01_60/
ts_102940v010201p.pdf".

[I-D.hinden-6man-rfc2464bis]
Crawford, M. and R. Hinden, "Transmission of IPv6 Packets
over Ethernet Networks", draft-hinden-6man-rfc2464bis-02
(work in progress), March 2017.

[I-D.ietf-ipwave-vehicular-networking-survey]
Jeong, J., Cespedes, S., Benamar, N., Haerri, J., and M.
Wetterwald, "Survey on IP-based Vehicular Networking for
Intelligent Transportation Systems are described Systems", draft-ietf-ipwave-
vehicular-networking-survey-00 (work in [ETSI-sec-archi].

As with all Ethernet progress), July
2017.

[I-D.perkins-intarea-multicast-ieee802]
Perkins, C., Stanley, D., Kumari, W., and 802.11 interface identifiers, there may
exist privacy risks in the use of 802.11-OCB interface identifiers.
Moreover, in outdoors vehicular settings, the privacy risks are more
important than J. Zuniga,
"Multicast Considerations over IEEE 802 Wireless Media",
draft-perkins-intarea-multicast-ieee802-03 (work in indoors settings. New risks are induced by the
possibility of attacker sniffers deployed along routes which listen
progress), July 2017.

[I-D.petrescu-its-scenarios-reqs]
Petrescu, A., Janneteau, C., Boc, M., and W. Klaudel,
"Scenarios and Requirements for IP packets of vehicles passing by. For this reason, in the
802.11-OCB deployments, there is a strong necessity to use protection
tools such as dynamically changing MAC addresses. This may help
mitigate privacy risks to a certain level. On another hand, it may
have an impact Intelligent
Transportation Systems", draft-petrescu-its-scenarios-
reqs-03 (work in progress), October 2013.

[IEEE-1609.2]
"IEEE SA - 1609.2-2016 - IEEE Standard for Wireless Access
in the way typical IPv6 address auto-configuration is
performed Vehicular Environments (WAVE) -- Security Services for vehicles (SLAAC would rely
Applications and Management Messages. Example URL
http://ieeexplore.ieee.org/document/7426684/ accessed on MAC addresses amd would
hence dynamically change the affected IP address),
August 17th, 2017.".

[IEEE-1609.3]
"IEEE SA - 1609.3-2016 - IEEE Standard for Wireless Access
in the way the
IPv6 Privacy addresses were used, Vehicular Environments (WAVE) -- Networking Services.
Example URL http://ieeexplore.ieee.org/document/7458115/
accessed on August 17th, 2017.".

[IEEE-1609.4]
"IEEE SA - 1609.4-2016 - IEEE Standard for Wireless Access
in Vehicular Environments (WAVE) -- Multi-Channel
Operation. Example URL
http://ieeexplore.ieee.org/document/7435228/ accessed on
August 17th, 2017.".

[IEEE-802.11-2016]
"IEEE Standard 802.11-2016 - IEEE Standard for Information
Technology - Telecommunications and other effects.

7. IANA Considerations

A Group ID named TBD, of length 112bits is requested to IANA; this
Group ID signifies "All 80211OCB Interfaces Address".

8. Contributors

Romain Kuntz contributed extensively about IPv6 handovers information exchange
between
links running outside systems Local and metropolitan area networks -
Specific requirements - Part 11: Wireless LAN Medium
Access Control (MAC) and Physical Layer (PHY)
Specifications. Status - Active Standard. Description
retrieved freely on September 12th, 2017, at URL
https://standards.ieee.org/findstds/
standard/802.11-2016.html".

[IEEE-802.11p-2010]
"IEEE Std 802.11p (TM)-2010, IEEE Standard for Information
Technology - Telecommunications and information exchange
between systems - Local and metropolitan area networks -
Specific requirements, Part 11: Wireless LAN Medium Access
Control (MAC) and Physical Layer (PHY) Specifications,
Amendment 6: Wireless Access in Vehicular Environments;
document freely available at URL
http://standards.ieee.org/getieee802/
download/802.11p-2010.pdf retrieved on September 20th,
2013.".

Appendix A. ChangeLog

The changes are listed in reverse chronological order, most recent
changes appearing at the context top of a BSS (802.11-OCB links).

Tim Leinmueller contributed the idea of list.

From draft-ietf-ipwave-ipv6-over-80211ocb-08 to draft-ietf-ipwave-
ipv6-over-80211ocb-09

o Significantly shortened the use of IPv6 over
802.11-OCB for distribution of certificates.

Marios Makassikis, Jose Santa Lozano, Albin Severinson Address Mapping sections, by text
copied from RFC2464, and Alexey
Voronov provided significant feedback rather referring to it.

o Moved the EPD description to an Appendix on its own.

o Shortened the experience of using IP
messages over 802.11-OCB in initial trials.

Michelle Wetterwald contributed extensively Introduction and the MTU discussion,
offered Abstract.

o Moved the ETSI ITS perspective, and reviewed other parts tutorial section of OCB mode introduced to .11, into an
appendix.

o Removed the
document.

9. Acknowledgements

The authors would like statement that suggests that for routing purposes a
prefix exchange mechanism could be needed.

o Removed refs to thank Witold Klaudel, Ryuji Wakikawa,
Emmanuel Baccelli, John Kenney, John Moring, Francois Simon, Dan
Romascanu, Konstantin Khait, Ralph Droms, Richard 'Dick' Roy, Ray
Hunter, Tom Kurihara, Michal Sojka, Jan de Jongh, Suresh Krishnan,
Dino Farinacci, Vincent Park, Jaehoon Paul Jeong, Gloria Gwynne,
Hans-Joachim Fischer, Russ Housley, Rex Buddenberg, Erik Nordmark,
Bob Moskowitz, Andrew (Dryden?), Georg Mayer, Dorothy Stanley, Sandra
Cespedes, Mariano Falcitelli, Sri Gundavelli RFC3963, RFC4429 and William Whyte.
Their valuable comments clarified particular issues RFC6775; these are about ND,
MIP/NEMO and generally
helped oDAD; they were referred in the handover discussion
section, which is out.

o Updated a reference from individual submission to improve now a WG item in
IPWAVE: the survey document.

Pierre Pfister, Rostislav Lisovy,

o Added term definition for WiFi.

o Updated the authorship and expanded the Contributors section.

o Corrected typographical errors.

From draft-ietf-ipwave-ipv6-over-80211ocb-07 to draft-ietf-ipwave-
ipv6-over-80211ocb-08

o Removed the per-channel IPv6 prohibition text.

o Corrected typographical errors.

From draft-ietf-ipwave-ipv6-over-80211ocb-06 to draft-ietf-ipwave-
ipv6-over-80211ocb-07

o Added new terms: OBRU and others, wrote 802.11-OCB
drivers RSRU ('R' for linux Router). Refined the
existing terms RSU and described how.

For OBU, which are no longer used throughout
the multicast discussion, document.

o Improved definition of term "802.11-OCB".

o Clarified that OCB does not "strip" security, but that the authors would like to thank Owen
DeLong, Joe Touch, Jen Linkova, Erik Kline, Brian Haberman and
participants to discussions
operation in network working groups.

The authours would like OCB mode is "stripped off of all .11 security".

o Clarified that theoretical OCB bandwidth speed is 54mbits, but
that a commonly observed bandwidth in IP-over-OCB is 12mbit/s.

o Corrected typographical errors, and improved some phrasing.

From draft-ietf-ipwave-ipv6-over-80211ocb-05 to thank participants draft-ietf-ipwave-
ipv6-over-80211ocb-06

o Updated references of 802.11-OCB document from -2012 to the Birds-of-
a-Feather "Intelligent Transportation Systems" meetings held at IETF IEEE
802.11-2016.

o In the LL address section, and in 2016.

10. References

10.1. Normative References

[I-D.ietf-tsvwg-ieee-802-11]
Szigeti, T., Henry, J., SLAAC section, added references
to 7217 opaque IIDs and F. Baker, "Diffserv 8064 stable IIDs.

From draft-ietf-ipwave-ipv6-over-80211ocb-04 to IEEE
802.11 Mapping", draft-ietf-tsvwg-ieee-802-11-09 (work in
progress), September 2017.

[RFC1042] Postel, J. draft-ietf-ipwave-
ipv6-over-80211ocb-05

o Lengthened the title and J. Reynolds, "Standard for cleanded the transmission
of IP datagrams over IEEE 802 networks", STD 43, RFC 1042,
DOI 10.17487/RFC1042, February 1988,
<https://www.rfc-editor.org/info/rfc1042>.

[RFC2119] Bradner, S., "Key words for use in RFCs abstract.

o Added text suggesting LLs may be easy to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.

[RFC2464] Crawford, M., "Transmission use on OCB, rather than
GUAs based on received prefix.

o Added the risks of IPv6 Packets over Ethernet
Networks", RFC 2464, DOI 10.17487/RFC2464, December 1998,
<https://www.rfc-editor.org/info/rfc2464>.

[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
DOI 10.17487/RFC2818, May 2000,
<https://www.rfc-editor.org/info/rfc2818>.

[RFC3753] Manner, J., Ed. spoofing and M. Kojo, Ed., "Mobility Related
Terminology", RFC 3753, DOI 10.17487/RFC3753, June 2004,
<https://www.rfc-editor.org/info/rfc3753>.

[RFC3963] Devarapalli, V., Wakikawa, R., Petrescu, A., hijacking.

o Removed the text speculation on adoption of the TSA message.

o Clarified that the ND protocol is used.

o Clarified what it means "No association needed".

o Added some text about how two STAs discover each other.

o Added mention of external (OCB) and P.
Thubert, "Network Mobility (NEMO) Basic Support Protocol",
RFC 3963, DOI 10.17487/RFC3963, January 2005,
<https://www.rfc-editor.org/info/rfc3963>.

[RFC3971] Arkko, J., Ed., Kempf, J., Zill, B., internal network (stable), in
the subnet structure section.

o Added phrase explaining that both .11 Data and P. Nikander,
"SEcure Neighbor Discovery (SEND)", RFC 3971,
DOI 10.17487/RFC3971, March 2005,
<https://www.rfc-editor.org/info/rfc3971>.

[RFC4086] Eastlake 3rd, D., Schiller, J., .11 QoS Data
headers are currently being used, and S. Crocker,
"Randomness Requirements may be used in the future.

o Moved the packet capture example into an Appendix Implementation
Status.

o Suggested moving the reliability requirements appendix out into
another document.

o Added a IANA Consiserations section, with content, requesting for Security", BCP 106, RFC 4086,
DOI 10.17487/RFC4086, June 2005,
<https://www.rfc-editor.org/info/rfc4086>.

[RFC4210] Adams, C., Farrell, S., Kause, T.,
a new multicast group "all OCB interfaces".

o Added new OBU term, improved the RSU term definition, removed the
ETTC term, replaced more occurences of 802.11p, 802.11 OCB with
802.11-OCB.

o References:

* Added an informational reference to ETSI's IPv6-over-
GeoNetworking.

* Added more references to IETF and T. Mononen,
"Internet X.509 Public Key Infrastructure Certificate
Management Protocol (CMP)", RFC 4210,
DOI 10.17487/RFC4210, September 2005,
<https://www.rfc-editor.org/info/rfc4210>.

[RFC4301] Kent, S. ETSI security protocols.

* Updated some references from I-D to RFC, and K. Seo, "Security Architecture for the
Internet Protocol", RFC 4301, DOI 10.17487/RFC4301,
December 2005, <https://www.rfc-editor.org/info/rfc4301>.

[RFC4302] Kent, S., "IP Authentication Header", from old RFC 4302,
DOI 10.17487/RFC4302, December 2005,
<https://www.rfc-editor.org/info/rfc4302>.

[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)", to
new RFC 4303, DOI 10.17487/RFC4303, December 2005,
<https://www.rfc-editor.org/info/rfc4303>.

[RFC4429] Moore, N., "Optimistic Duplicate Address Detection (DAD) numbers.

* Added reference to multicast extensions to IPsec architecture
RFC.

* Added a reference to 2464-bis.

* Removed FCC informative references, because not used.

o Updated the affiliation of one author.

o Reformulation of some phrases for IPv6", RFC 4429, DOI 10.17487/RFC4429, April 2006,
<https://www.rfc-editor.org/info/rfc4429>.

[RFC4861] Narten, T., Nordmark, E., Simpson, W., better readability, and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.

[RFC5374] Weis, B., Gross, G.,
correction of typographical errors.

From draft-ietf-ipwave-ipv6-over-80211ocb-03 to draft-ietf-ipwave-
ipv6-over-80211ocb-04

o Removed a few informative references pointing to Dx draft IEEE
1609 documents.

o Removed outdated informative references to ETSI documents.

o Added citations to IEEE 1609.2, .3 and D. Ignjatic, "Multicast
Extensions .4-2016.

o Minor textual issues.

From draft-ietf-ipwave-ipv6-over-80211ocb-02 to draft-ietf-ipwave-
ipv6-over-80211ocb-03

o Keep the previous text on multiple addresses, so remove talk about
MIP6, NEMOv6 and MCoA.

o Clarified that a 'Beacon' is an IEEE 802.11 frame Beacon.

o Clarified the figure showing Infrastructure mode and OCB mode side
by side.

o Added a reference to the IP Security Architecture RFC.

o Detailed the IPv6-per-channel prohibition paragraph which reflects
the discussion at the last IETF IPWAVE WG meeting.

o Added section "Address Mapping -- Unicast".

o Added the ".11 Trailer" to pictures of 802.11 frames.

o Added text about SNAP carrying the Security Architecture Ethertype.

o New RSU definition allowing for the Internet
Protocol", RFC 5374, DOI 10.17487/RFC5374, November 2008,
<https://www.rfc-editor.org/info/rfc5374>.

[RFC5415] Calhoun, P., Ed., Montemurro, M., Ed., it be both a Router and D. Stanley,
Ed., "Control And Provisioning not
necessarily a Router some times.

o Minor textual issues.

From draft-ietf-ipwave-ipv6-over-80211ocb-01 to draft-ietf-ipwave-
ipv6-over-80211ocb-02

o Replaced almost all occurences of Wireless Access Points
(CAPWAP) Protocol Specification", RFC 5415,
DOI 10.17487/RFC5415, March 2009,
<https://www.rfc-editor.org/info/rfc5415>.

[RFC5889] Baccelli, E., Ed. and M. Townsley, Ed., "IP Addressing
Model 802.11p with 802.11-OCB, leaving
only when explanation of evolution was necessary.

o Shortened by removing parameter details from a paragraph in Ad Hoc Networks", RFC 5889, DOI 10.17487/RFC5889,
September 2010, <https://www.rfc-editor.org/info/rfc5889>.

[RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility
Support the
Introduction.

o Moved a reference from Normative to Informative.

o Added text in IPv6", RFC 6275, DOI 10.17487/RFC6275, July
2011, <https://www.rfc-editor.org/info/rfc6275>.

[RFC6775] Shelby, Z., Ed., Chakrabarti, S., Nordmark, E., intro clarifying there is no handover spec at IEEE,
and C.
Bormann, "Neighbor Discovery Optimization for IPv6 over
Low-Power Wireless Personal Area Networks (6LoWPANs)",
RFC 6775, DOI 10.17487/RFC6775, November 2012,
<https://www.rfc-editor.org/info/rfc6775>.

[RFC7136] Carpenter, B. that 1609.2 does provide security services.

o Named the contents the fields of the EthernetII header (including
the Ethertype bitstring).

o Improved relationship between two paragraphs describing the
increase of the Sequence Number in 802.11 header upon IP
fragmentation.

o Added brief clarification of "tracking".

From draft-ietf-ipwave-ipv6-over-80211ocb-00 to draft-ietf-ipwave-
ipv6-over-80211ocb-01

o Introduced message exchange diagram illustrating differences
between 802.11 and S. Jiang, "Significance of IPv6
Interface Identifiers", RFC 7136, DOI 10.17487/RFC7136,
February 2014, <https://www.rfc-editor.org/info/rfc7136>.

[RFC7217] Gont, F., "A Method 802.11 in OCB mode.

o Introduced an appendix listing for Generating Semantically Opaque
Interface Identifiers with IPv6 Stateless Address
Autoconfiguration (SLAAC)", RFC 7217,
DOI 10.17487/RFC7217, April 2014,
<https://www.rfc-editor.org/info/rfc7217>.

[RFC7721] Cooper, A., Gont, F., information the set of 802.11
messages that may be transmitted in OCB mode.

o Removed appendix sections "Privacy Requirements", "Authentication
Requirements" and D. Thaler, "Security and Privacy Certificate Generation".

o Removed appendix section "Non IP Communications".

o Introductory phrase in the Security Considerations for IPv6 Address Generation Mechanisms",
RFC 7721, DOI 10.17487/RFC7721, March 2016,
<https://www.rfc-editor.org/info/rfc7721>.

[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.

10.2. Informative References

o Improved the definition of IPv6 Packets over
Geonetworking Protocols. Downloaded on September 9th,
2017, freely available from ETSI website at URL
http://www.etsi.org/deliver/
etsi_en/302600_302699/30263601/01.02.01_60/
en_30263601v010201p.pdf".

[ETSI-sec-archi]
"ETSI TS 102 940 V1.2.1 (2016-11), ETSI Technical
Specification, Intelligent Transport Systems (ITS);
Security; ITS communications security architecture and
security management, November 2016. Dowloaded on
September 9th, 2017, freely available from ETSI website at
URL http://www.etsi.org/deliver/
etsi_ts/102900_102999/102940/01.02.01_60/
ts_102940v010201p.pdf".

[I-D.hinden-6man-rfc2464bis]
Crawford, M. "OCB".

o Introduced theoretical stacked layers about IPv6 and R. Hinden, "Transmission IEEE layers
including EPD.

o Removed the appendix describing the details of prohibiting IPv6 Packets
over Ethernet Networks", draft-hinden-6man-rfc2464bis-02
(work in progress), March 2017.

[I-D.jeong-ipwave-vehicular-networking-survey]
Jeong, J., Cespedes, S., Benamar, N., Haerri, J., and M.
Wetterwald, "Survey on IP-based Vehicular Networking for
Intelligent Transportation Systems", draft-jeong-ipwave-
vehicular-networking-survey-03 (work
certain channels relevant to 802.11-OCB.

o Added a brief reference in progress), June
2017.

[I-D.perkins-intarea-multicast-ieee802]
Perkins, C., Stanley, D., Kumari, W., and J. Zuniga,
"Multicast Considerations over IEEE 802 Wireless Media",
draft-perkins-intarea-multicast-ieee802-03 (work the privacy text about a precise clause
in
progress), July 2017.

[I-D.petrescu-its-scenarios-reqs]
Petrescu, A., Janneteau, C., Boc, M., IEEE 1609.3 and W. Klaudel,
"Scenarios .4.

o Clarified the definition of a Road Side Unit.

o Removed the discussion about security of WSA (because is non-IP).

o Removed mentioning of the GeoNetworking discussion.

o Moved references to scientific articles to a separate 'overview'
draft, and Requirements for IP in Intelligent
Transportation Systems", draft-petrescu-its-scenarios-
reqs-03 (work referred to it.

Appendix B. 802.11p

The term "802.11p" is an earlier definition. The behaviour of
"802.11p" networks is rolled in progress), October 2013.

[IEEE-1609.2]
"IEEE SA - 1609.2-2016 - the document IEEE Std 802.11-2016.
In that document the term 802.11p disappears. Instead, each 802.11p
feature is conditioned by the Management Information Base (MIB)
attribute "OCBActivated". Whenever OCBActivated is set to true the
IEEE Std 802.11 OCB state is activated. For example, an 802.11
STAtion operating outside the context of a basic service set has the
OCBActivated flag set. Such a station, when it has the flag set,
uses a BSS identifier equal to ff:ff:ff:ff:ff:ff.

Appendix C. Aspects introduced by the OCB mode to 802.11

In the IEEE Standard for Wireless Access 802.11-OCB mode, all nodes in Vehicular Environments (WAVE) -- Security Services for
Applications the wireless range can
directly communicate with each other without involving authentication
or association procedures. At link layer, it is necessary to set the
same channel number (or frequency) on two stations that need to
communicate with each other. Stations STA1 and Management Messages. Example URL
http://ieeexplore.ieee.org/document/7426684/ accessed STA2 can exchange IP
packets if they are set on
August 17th, 2017.".

[IEEE-1609.3]
"IEEE SA - 1609.3-2016 - the same channel. At IP layer, they then
discover each other by using the IPv6 Neighbor Discovery protocol.

Briefly, the IEEE Standard for Wireless Access
in Vehicular Environments (WAVE) -- Networking Services.
Example URL http://ieeexplore.ieee.org/document/7458115/
accessed on August 17th, 2017.".

[IEEE-1609.4]
"IEEE SA - 1609.4-2016 - 802.11-OCB mode has the following properties:

o The use by each node of a 'wildcard' BSSID (i.e., each bit of the
BSSID is set to 1)

o No IEEE Standard for Wireless Access 802.11 Beacon frames are transmitted

o No authentication is required in Vehicular Environments (WAVE) -- Multi-Channel
Operation. Example URL
http://ieeexplore.ieee.org/document/7435228/ accessed on
August 17th, 2017.".

[IEEE-802.11-2016]
"IEEE Standard 802.11-2016 - IEEE Standard for Information
Technology - Telecommunications order to be able to communicate

o No association is needed in order to be able to communicate

o No encryption is provided in order to be able to communicate

o Flag dot11OCBActivated is set to true

All the nodes in the radio communication range (OBRU and RSRU)
receive all the messages transmitted (OBRU and information RSRU) within the radio
communications range. The eventual conflict(s) are resolved by the
MAC CDMA function.

The following message exchange diagram illustrates a comparison
between systems Local traditional 802.11 and metropolitan area networks -
Specific requirements - Part 11: Wireless LAN Medium
Access Control (MAC) 802.11 in OCB mode. The 'Data'
messages can be IP packets such as HTTP or others. Other 802.11
management and Physical Layer (PHY)
Specifications. Status - Active Standard. Description
retrieved freely on September 12th, 2017, at URL
https://standards.ieee.org/findstds/
standard/802.11-2016.html".

[IEEE-802.11p-2010]
"IEEE control frames (non IP) may be transmitted, as
specified in the 802.11 standard. For information, the names of
these messages as currently specified by the 802.11 standard are
listed in Appendix G.

STA AP STA1 STA2
| | | |
|<------ Beacon -------| |<------ Data -------->|
| | | |
|---- Probe Req. ----->| |<------ Data -------->|
|<--- Probe Res. ------| | |
| | |<------ Data -------->|
|---- Auth Req. ------>| | |
|<--- Auth Res. -------| |<------ Data -------->|
| | | |
|---- Asso Req. ------>| |<------ Data -------->|
|<--- Asso Res. -------| | |
| | |<------ Data -------->|
|<------ Data -------->| | |
|<------ Data -------->| |<------ Data -------->|

(a) 802.11 Infrastructure mode (b) 802.11-OCB mode

The interface 802.11-OCB was specified in IEEE Std 802.11p (TM)-2010, (TM) -2010
[IEEE-802.11p-2010] as an amendment to IEEE Standard for Information
Technology - Telecommunications and information exchange
between systems - Local and metropolitan area networks -
Specific requirements, Part 11: Wireless LAN Medium Access
Control (MAC) and Physical Layer (PHY) Specifications,
Amendment Std 802.11 (TM) -2007,
titled "Amendment 6: Wireless Access in Vehicular Environments;
document freely available at URL
http://standards.ieee.org/getieee802/
download/802.11p-2010.pdf retrieved on September 20th,
2013.".

Appendix A. ChangeLog

The changes are listed Environments".
Since then, this amendment has been included in reverse chronological order, most recent
changes appearing at IEEE 802.11(TM) -2012
and -2016 [IEEE-802.11-2016].

In document 802.11-2016, anything qualified specifically as
"OCBActivated", or "outside the top context of the list.

From draft-ietf-ipwave-ipv6-over-80211ocb-07 a basic service" set to draft-ietf-ipwave-
ipv6-over-80211ocb-08

o Removed be
true, then it is actually referring to OCB aspects introduced to
802.11.

In order to delineate the per-channel IPv6 prohibition text.

o Corrected typographical errors.

From draft-ietf-ipwave-ipv6-over-80211ocb-06 aspects introduced by 802.11-OCB to 802.11,
we refer to draft-ietf-ipwave-
ipv6-over-80211ocb-07

o Added new terms: OBRU and RSRU ('R' for Router). Refined the
existing terms RSU and OBU, which are no longer used throughout earlier [IEEE-802.11p-2010]. The amendment is
concerned with vehicular communications, where the document.

o Improved definition of term "802.11-OCB".

o Clarified wireless link is
similar to that OCB does not "strip" security, of Wireless LAN (using a PHY layer specified by
802.11a/b/g/n), but that which needs to cope with the
operation high mobility factor
inherent in OCB mode is "stripped off scenarios of all .11 security".

o Clarified that theoretical OCB bandwidth speed communications between moving vehicles, and
between vehicles and fixed infrastructure deployed along roads.
While 'p' is 54mbits, but
that a commonly observed bandwidth in IP-over-OCB letter just like 'a, b, g' and 'n' are, 'p' is 12mbit/s.

o Corrected typographical errors,
concerned more with MAC modifications, and improved some phrasing.

From draft-ietf-ipwave-ipv6-over-80211ocb-05 a little with PHY
modifications; the others are mainly about PHY modifications. It is
possible in practice to draft-ietf-ipwave-
ipv6-over-80211ocb-06

o Updated references combine a 'p' MAC with an 'a' PHY by
operating outside the context of a BSS with OFDM at 5.4GHz and
5.9GHz.

The 802.11-OCB document from -2012 links are specified to be compatible as much as
possible with the IEEE
802.11-2016.

o In the LL address section, and in SLAAC section, added references
to 7217 opaque IIDs behaviour of 802.11a/b/g/n and 8064 stable IIDs. future generation
IEEE WLAN links. From draft-ietf-ipwave-ipv6-over-80211ocb-04 the IP perspective, an 802.11-OCB MAC layer
offers practically the same interface to draft-ietf-ipwave-
ipv6-over-80211ocb-05

o Lengthened IP as the title WiFi and cleanded the abstract.

o Added text suggesting LLs Ethernet
layers do (802.11a/b/g/n and 802.3). A packet sent by an OBRU may be easy to use on OCB, rather than
GUAs based on
received prefix.

o Added by one or multiple RSRUs. The link-layer resolution is
performed by using the risks IPv6 Neighbor Discovery protocol.

To support this similarity statement (IPv6 is layered on top of spoofing and hijacking.

o Removed the text speculation LLC
on adoption top of 802.11-OCB, in the TSA message.

o Clarified same way that the ND protocol IPv6 is used.

o Clarified what it means "No association needed".

o Added some text about how two STAs discover each other.

o Added mention layered on top of external (OCB) and internal network (stable), in
LLC on top of 802.11a/b/g/n (for WLAN) or layered on top of LLC on
top of 802.3 (for Ethernet)) it is useful to analyze the subnet structure section.

o Added phrase explaining differences
between 802.11-OCB and 802.11 specifications. During this analysis,
we note that both .11 Data whereas 802.11-OCB lists relatively complex and .11 QoS Data
headers numerous
changes to the MAC layer (and very little to the PHY layer), there
are currently being used, and only a few characteristics which may be used in important for an
implementation transmitting IPv6 packets on 802.11-OCB links.

The most important 802.11-OCB point which influences the future.

o Moved IPv6
functioning is the packet capture example into OCB characteristic; an Appendix Implementation
Status.

o Suggested moving additional, less direct
influence, is the reliability requirements appendix out into
another document.

o Added a IANA Consiserations section, with content, requesting maximum bandwidth afforded by the PHY modulation/
demodulation methods and channel access specified by 802.11-OCB. The
maximum bandwidth theoretically possible in 802.11-OCB is 54 Mbit/s
(when using, for
a new multicast group "all OCB interfaces".

o Added new OBU term, improved example, the RSU term definition, removed following parameters: 20 MHz channel;
modulation 64-QAM; codint rate R is 3/4); in practice of IP-over-
802.11-OCB a commonly observed figure is 12Mbit/s; this bandwidth
allows the
ETTC term, replaced more occurences operation of 802.11p, 802.11 OCB with
802.11-OCB. a wide range of protocols relying on IPv6.

o References:

* Added an informational reference to ETSI's IPv6-over-
GeoNetworking.

* Added more references to IETF and ETSI security protocols.

* Updated some references from I-D to RFC, and from old RFC to
new RFC numbers.

* Added reference to multicast extensions to IPsec architecture
RFC.

* Added Operation Outside the Context of a reference to 2464-bis.

* Removed FCC informative references, because BSS (OCB): the (earlier
802.11p) 802.11-OCB links are operated without a Basic Service Set
(BSS). This means that the frames IEEE 802.11 Beacon, Association
Request/Response, Authentication Request/Response, and similar,
are not used.

o Updated the affiliation The used identifier of one author.

o Reformulation BSS (BSSID) has a
hexadecimal value always 0xffffffffffff (48 '1' bits, represented
as MAC address ff:ff:ff:ff:ff:ff, or otherwise the 'wildcard'
BSSID), as opposed to an arbitrary BSSID value set by
administrator (e.g. 'My-Home-AccessPoint'). The OCB operation -
namely the lack of some phrases for better readability, beacon-based scanning and
correction lack of typographical errors.

From draft-ietf-ipwave-ipv6-over-80211ocb-03
authentication - should be taken into account when the Mobile IPv6
protocol [RFC6275] and the protocols for IP layer security
[RFC4301] are used. The way these protocols adapt to draft-ietf-ipwave-
ipv6-over-80211ocb-04 OCB is not
described in this document.

o Removed Timing Advertisement: is a few informative references pointing to Dx draft IEEE
1609 documents.

o Removed outdated informative references to ETSI documents.

o Added citations to IEEE 1609.2, .3 and .4-2016.

o Minor textual issues.

From draft-ietf-ipwave-ipv6-over-80211ocb-02 new message defined in 802.11-OCB,
which does not exist in 802.11a/b/g/n. This message is used by
stations to draft-ietf-ipwave-
ipv6-over-80211ocb-03

o Keep the previous text on multiple addresses, so remove talk inform other stations about
MIP6, NEMOv6 and MCoA.

o Clarified that a 'Beacon' the value of time. It is an IEEE 802.11 frame Beacon.

o Clarified
similar to the figure showing Infrastructure mode and OCB mode side time as delivered by side. a GNSS system (Galileo, GPS,
...) or by a cellular system. This message is optional for
implementation.

o Added Frequency range: this is a reference to characteristic of the IP Security Architecture RFC.

o Detailed PHY layer, with
almost no impact on the IPv6-per-channel prohibition paragraph which reflects interface between MAC and IP. However, it
is worth considering that the discussion at frequency range is regulated by a
regional authority (ARCEP, ETSI, FCC, etc.); as part of the last IETF IPWAVE WG meeting.

o Added section "Address Mapping -- Unicast".

o Added
regulation process, specific applications are associated with
specific frequency ranges. In the ".11 Trailer" to pictures case of 802.11 frames.

o Added text about SNAP carrying 802.11-OCB, the Ethertype.

o New RSU definition allowing for it be both
regulator associates a Router and not
necessarily set of frequency ranges, or slots within a Router some times.

o Minor textual issues.

From draft-ietf-ipwave-ipv6-over-80211ocb-01
band, to draft-ietf-ipwave-
ipv6-over-80211ocb-02

o Replaced almost all occurences the use of 802.11p with 802.11-OCB, leaving
only when explanation applications of evolution was necessary.

o Shortened vehicular communications, in a
band known as "5.9GHz". The 5.9GHz band is different from the
2.4GHz and 5GHz bands used by removing parameter details Wireless LAN. However, as with
Wireless LAN, the operation of 802.11-OCB in "5.9GHz" bands is
exempt from owning a paragraph license in EU (in US the
Introduction.

o Moved 5.9GHz is a reference from Normative to Informative.

o Added text in intro clarifying there licensed
band of spectrum; for the fixed infrastructure an explicit FCC
autorization is no handover spec at IEEE,
and that 1609.2 does provide security services.

o Named required; for an onboard device a 'licensed-by-
rule' concept applies: rule certification conformity is required);
however technical conditions are different than those of the contents bands
"2.4GHz" or "5GHz". On one hand, the allowed power levels, and
implicitly the fields maximum allowed distance between vehicles, is of
33dBm for 802.11-OCB (in Europe), compared to 20 dBm for Wireless
LAN 802.11a/b/g/n; this leads to a maximum distance of
approximately 1km, compared to approximately 50m. On the EthernetII header (including
the Ethertype bitstring).

o Improved relationship between two paragraphs describing other
hand, specific conditions related to congestion avoidance, jamming
avoidance, and radar detection are imposed on the
increase use of DSRC (in
US) and on the Sequence Number in 802.11 header upon IP
fragmentation.

o Added brief clarification use of "tracking".

From draft-ietf-ipwave-ipv6-over-80211ocb-00 frequencies for Intelligent Transportation
Systems (in EU), compared to draft-ietf-ipwave-
ipv6-over-80211ocb-01

o Introduced message exchange diagram illustrating differences
between 802.11 and 802.11 in OCB mode. Wireless LAN (802.11a/b/g/n).

o Introduced an appendix listing for information 'Half-rate' encoding: as the set of 802.11
messages that may be transmitted in OCB mode.

o Removed appendix sections "Privacy Requirements", "Authentication
Requirements" frequency range, this parameter is
related to PHY, and "Security Certificate Generation".

o Removed appendix section "Non IP Communications".

o Introductory phrase in thus has not much impact on the Security Considerations section.

o Improved interface
between the definition of "OCB".

o Introduced theoretical stacked layers about IPv6 IP layer and IEEE layers
including EPD.

o Removed the appendix describing MAC layer.

o In vehicular communications using 802.11-OCB links, there are
strong privacy requirements with respect to addressing. While the details of prohibiting IPv6 on
certain channels relevant
802.11-OCB standard does not specify anything in particular with
respect to 802.11-OCB.

o Added a brief reference MAC addresses, in these settings there exists a strong
need for dynamic change of these addresses (as opposed to the non-
vehicular settings - real wall protection - where fixed MAC
addresses do not currently pose some privacy text about a precise clause risks). This is
further described in section Section 5. A relevant function is
described in IEEE 1609.3 1609.3-2016 [IEEE-1609.3], clause 5.5.1 and .4.

o Clarified IEEE
1609.4-2016 [IEEE-1609.4], clause 6.7.

Other aspects particular to 802.11-OCB, which are also particular to
802.11 (e.g. the definition of a Road Side Unit.

o Removed 'hidden node' operation), may have an influence on
the discussion about security use of WSA (because is non-IP).

o Removed mentioning transmission of the GeoNetworking discussion.

o Moved references to scientific articles to a separate 'overview'
draft, and referred to it. IPv6 packets on 802.11-OCB networks. The
OCB subnet structure is described in section Section 4.6.

Appendix B. D. Changes Needed on a software driver 802.11a to become a
802.11-OCB driver

The 802.11p amendment modifies both the 802.11 stack's physical and
MAC layers but all the induced modifications can be quite easily
obtained by modifying an existing 802.11a ad-hoc stack.

Conditions for a 802.11a hardware to be 802.11-OCB compliant:

o The PHY entity shall be an orthogonal frequency division
multiplexing (OFDM) system. It must support the frequency bands
on which the regulator recommends the use of ITS communications,
for example using IEEE 802.11-OCB layer, in France: 5875MHz to
5925MHz.

o The OFDM system must provide a "half-clocked" operation using 10
MHz channel spacings.

o The chip transmit spectrum mask must be compliant to the "Transmit
spectrum mask" from the IEEE 802.11p amendment (but experimental
environments tolerate otherwise).

o The chip should be able to transmit up to 44.8 dBm when used by
the US government in the United States, and up to 33 dBm in
Europe; other regional conditions apply.

Changes needed on the network stack in OCB mode:

o Physical layer:

* The chip must use the Orthogonal Frequency Multiple Access
(OFDM) encoding mode.

* The chip must be set in half-mode rate mode (the internal clock
frequency is divided by two).

* The chip must use dedicated channels and should allow the use
of higher emission powers. This may require modifications to
the local computer file that describes regulatory domains
rules, if used by the kernel to enforce local specific
restrictions. Such modifications to the local computer file
must respect the location-specific regulatory rules.

MAC layer:

* All management frames (beacons, join, leave, and others)
emission and reception must be disabled except for frames of
subtype Action and Timing Advertisement (defined below).

* No encryption key or method must be used.

* Packet emission and reception must be performed as in ad-hoc
mode, using the wildcard BSSID (ff:ff:ff:ff:ff:ff).

* The functions related to joining a BSS (Association Request/
Response) and for authentication (Authentication Request/Reply,
Challenge) are not called.

* The beacon interval is always set to 0 (zero).

* Timing Advertisement frames, defined in the amendment, should
be supported. The upper layer should be able to trigger such
frames emission and to retrieve information contained in
received Timing Advertisements.

Appendix C. E. EPD

A more theoretical and detailed view of layer stacking, and
interfaces between the IP layer and 802.11-OCB layers, is illustrated
below. The IP layer operates on top of the EtherType Protocol
Discrimination (EPD); this Discrimination layer is described in IEEE
Std 802.3-2012; the interface between IPv6 and EPD is the LLC_SAP
(Link Layer Control Service Access Point).

Appendix F. Design Considerations

The networks defined by 802.11-OCB are in many ways similar to other
networks of the 802.11 family. In theory, the encapsulation of IPv6
over 802.11-OCB could be very similar to the operation of IPv6 over
other networks of the 802.11 family. However, the high mobility,
strong link asymmetry and very short connection makes the 802.11-OCB
link significantly different from other 802.11 networks. Also, the
automotive applications have specific requirements for reliability,
security and privacy, which further add to the particularity of the
802.11-OCB link.

C.1.

F.1. Vehicle ID

In automotive networks it is required that each node is represented
uniquely. Accordingly, a vehicle must be identified by at least one
unique identifier. The current specification at ETSI and at IEEE
1609 identifies a vehicle by its MAC address, which is obtained from
the 802.11-OCB Network Interface Card (NIC).

In case multiple 802.11-OCB NICs are present in one car, implicitely
multiple vehicle IDs will be generated. Additionally, some software
generates a random MAC address each time the computer boots; this
constitutes an additional difficulty.

A mechanim to uniquely identify a vehicle irrespectively to the
multiplicity of NICs, or frequent MAC address generation, is
necessary.

C.2.

F.2. Reliability Requirements

This section may need to be moved out into a separate requirements
document.

The dynamically changing topology, short connectivity, mobile
transmitter and receivers, different antenna heights, and many-to-
many communication types, make IEEE 802.11-OCB links significantly
different from other IEEE 802.11 links. Any IPv6 mechanism operating
on IEEE 802.11-OCB link MUST support strong link asymmetry, spatio-
temporal link quality, fast address resolution and transmission.

IEEE 802.11-OCB strongly differs from other 802.11 systems to operate
outside of the context of a Basic Service Set. This means in
practice that IEEE 802.11-OCB does not rely on a Base Station for all
Basic Service Set management. In particular, IEEE 802.11-OCB SHALL
NOT use beacons. Any IPv6 mechanism requiring L2 services from IEEE
802.11 beacons MUST support an alternative service.

Channel scanning being disabled, IPv6 over IEEE 802.11-OCB MUST
implement a mechanism for transmitter and receiver to converge to a
common channel.

Authentication not being possible, IPv6 over IEEE 802.11-OCB MUST
implement an distributed mechanism to authenticate transmitters and
receivers without the support of a DHCP server.

Time synchronization not being available, IPv6 over IEEE 802.11-OCB
MUST implement a higher layer mechanism for time synchronization
between transmitters and receivers without the support of a NTP
server.

The IEEE 802.11-OCB link being asymmetric, IPv6 over IEEE 802.11-OCB
MUST disable management mechanisms requesting acknowledgements or
replies.

The IEEE 802.11-OCB link having a short duration time, IPv6 over IEEE
802.11-OCB SHOULD implement fast IPv6 mobility management mechanisms.

C.3.

F.3. Multiple interfaces

There are considerations for 2 or more IEEE 802.11-OCB interface
cards per vehicle. For each vehicle taking part in road traffic, one
IEEE 802.11-OCB interface card could be fully allocated for Non IP
safety-critical communication. Any other IEEE 802.11-OCB may be used
for other type of traffic.

The mode of operation of these other wireless interfaces is not
clearly defined yet. One possibility is to consider each card as an
independent network interface, with a specific MAC Address and a set
of IPv6 addresses. Another possibility is to consider the set of
these wireless interfaces as a single network interface (not
including the IEEE 802.11-OCB interface used by Non IP safety
critical communications). This will require specific logic to
ensure, for example, that packets meant for a vehicle in front are
actually sent by the radio in the front, or that multiple copies of
the same packet received by multiple interfaces are treated as a
single packet. Treating each wireless interface as a separate
network interface pushes such issues to the application layer.

Certain privacy requirements imply that if these multiple interfaces
are represented by many network interface, a single renumbering event
SHALL cause renumbering of all these interfaces. If one MAC changed
and another stayed constant, external observers would be able to
correlate old and new values, and the privacy benefits of
randomization would be lost.

The privacy requirements of Non IP safety-critical communications
imply that if a change of pseudonyme occurs, renumbering of all other
interfaces SHALL also occur.

C.4.

F.4. MAC Address Generation

When designing the IPv6 over 802.11-OCB address mapping, we will
assume that the MAC Addresses will change during well defined
"renumbering events". The 48 bits randomized MAC addresses will have
the following characteristics:

o Bit "Local/Global" set to "locally admninistered".

o Bit "Unicast/Multicast" set to "Unicast".

o 46 remaining bits set to a random value, using a random number
generator that meets the requirements of [RFC4086].

The way to meet the randomization requirements is to retain 46 bits
from the output of a strong hash function, such as SHA256, taking as
input a 256 bit local secret, the "nominal" MAC Address of the
interface, and a representation of the date and time of the
renumbering event.

Appendix D. G. IEEE 802.11 Messages Transmitted in OCB mode

For information, at the time of writing, this is the list of IEEE
802.11 messages that may be transmitted in OCB mode, i.e. when
dot11OCBActivated is true in a STA:

o The STA may send management frames of subtype Action and, if the
STA maintains a TSF Timer, subtype Timing Advertisement;

o The STA may send control frames, except those of subtype PS-Poll,
CF-End, and CF-End plus CFAck;

o The STA may send data frames of subtype Data, Null, QoS Data, and
QoS Null.

Appendix E. H. Implementation Status

This section describes an example of an IPv6 Packet captured over a
IEEE 802.11-OCB link.

By way of example we show that there is no modification in the
headers when transmitted over 802.11-OCB networks - they are
transmitted like any other 802.11 and Ethernet packets.

We describe an experiment of capturing an IPv6 packet on an
802.11-OCB link. In this experiment, the packet is an IPv6 Router
Advertisement. This packet is emitted by a Router on its 802.11-OCB
interface. The packet is captured on the Host, using a network
protocol analyzer (e.g. Wireshark); the capture is performed in two
different modes: direct mode and 'monitor' mode. The topology used
during the capture is depicted below.

+--------+ +-------+
| | 802.11-OCB Link | |
---| Router |--------------------------------| Host |
| | | |
+--------+ +-------+

During several capture operations running from a few moments to
several hours, no message relevant to the BSSID contexts were
captured (no Association Request/Response, Authentication Req/Resp,
Beacon). This shows that the operation of 802.11-OCB is outside the
context of a BSSID.

Overall, the captured message is identical with a capture of an IPv6
packet emitted on a 802.11b interface. The contents are precisely
similar.

E.1.

H.1. Capture in Monitor Mode

The IPv6 RA packet captured in monitor mode is illustrated below.
The radio tap header provides more flexibility for reporting the
characteristics of frames. The Radiotap Header is prepended by this
particular stack and operating system on the Host machine to the RA
packet received from the network (the Radiotap Header is not present
on the air). The implementation-dependent Radiotap Header is useful
for piggybacking PHY information from the chip's registers as data in
a packet understandable by userland applications using Socket
interfaces (the PHY interface can be, for example: power levels, data
rate, ratio of signal to noise).

The packet present on the air is formed by IEEE 802.11 Data Header,
Logical Link Control Header, IPv6 Base Header and ICMPv6 Header.

Radiotap Header v0
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Header Revision| Header Pad | Header length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Present flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data Rate | Pad |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
IEEE 802.11 Data Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type/Subtype and Frame Ctrl | Duration |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Receiver Address...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
... Receiver Address | Transmitter Address...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
... Transmitter Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BSS Id...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
... BSS Id | Frag Number and Seq Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

IPv6 Base Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| Traffic Class | Flow Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Payload Length | Next Header | Hop Limit |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Source Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Destination Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The value of the Data Rate field in the Radiotap header is set to 6
Mb/s. This indicates the rate at which this RA was received.

The value of the Transmitter address in the IEEE 802.11 Data Header
is set to a 48bit value. The value of the destination address is
33:33:00:00:00:1 (all-nodes multicast address). The value of the BSS
Id field is ff:ff:ff:ff:ff:ff, which is recognized by the network
protocol analyzer as being "broadcast". The Fragment number and
sequence number fields are together set to 0x90C6.

The value of the Organization Code field in the Logical-Link Control
Header is set to 0x0, recognized as "Encapsulated Ethernet". The
value of the Type field is 0x86DD (hexadecimal 86DD, or otherwise
#86DD), recognized as "IPv6".

A Router Advertisement is periodically sent by the router to
multicast group address ff02::1. It is an icmp packet type 134. The
IPv6 Neighbor Discovery's Router Advertisement message contains an
8-bit field reserved for single-bit flags, as described in [RFC4861].

The IPv6 header contains the link local address of the router
(source) configured via EUI-64 algorithm, and destination address set
to ff02::1. Recent versions of network protocol analyzers (e.g.
Wireshark) provide additional informations for an IP address, if a
geolocalization database is present. In this example, the
geolocalization database is absent, and the "GeoIP" information is
set to unknown for both source and destination addresses (although
the IPv6 source and destination addresses are set to useful values).
This "GeoIP" can be a useful information to look up the city,
country, AS number, and other information for an IP address.

The Ethernet Type field in the logical-link control header is set to
0x86dd which indicates that the frame transports an IPv6 packet. In
the IEEE 802.11 data, the destination address is 33:33:00:00:00:01
which is the corresponding multicast MAC address. The BSS id is a
broadcast address of ff:ff:ff:ff:ff:ff. Due to the short link
duration between vehicles and the roadside infrastructure, there is
no need in IEEE 802.11-OCB to wait for the completion of association
and authentication procedures before exchanging data. IEEE
802.11-OCB enabled nodes use the wildcard BSSID (a value of all 1s)
and may start communicating as soon as they arrive on the
communication channel.

E.2.

H.2. Capture in Normal Mode

The same IPv6 Router Advertisement packet described above (monitor
mode) is captured on the Host, in the Normal mode, and depicted
below.

Ethernet II Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Destination...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
...Destination | Source...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
...Source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

One notices that the Radiotap Header, the IEEE 802.11 Data Header and
the Logical-Link Control Headers are not present. On the other hand,
a new header named Ethernet II Header is present.

The Destination and Source addresses in the Ethernet II header
contain the same values as the fields Receiver Address and
Transmitter Address present in the IEEE 802.11 Data Header in the
"monitor" mode capture.

The value of the Type field in the Ethernet II header is 0x86DD
(recognized as "IPv6"); this value is the same value as the value of
the field Type in the Logical-Link Control Header in the "monitor"
mode capture.

The knowledgeable experimenter will no doubt notice the similarity of
this Ethernet II Header with a capture in normal mode on a pure
Ethernet cable interface.

An Adaptation layer is inserted on top of a pure IEEE 802.11 MAC
layer, in order to adapt packets, before delivering the payload data
to the applications. It adapts 802.11 LLC/MAC headers to Ethernet II
headers. In further detail, this adaptation consists in the
elimination of the Radiotap, 802.11 and LLC headers, and in the
insertion of the Ethernet II header. In this way, IPv6 runs straight
over LLC over the 802.11-OCB MAC layer; this is further confirmed by
the use of the unique Type 0x86DD.

Authors' Addresses

Alexandre Petrescu
CEA, LIST
CEA Saclay
Gif-sur-Yvette , Ile-de-France 91190
France

Phone: +33169089223
Email: Alexandre.Petrescu@cea.fr

Nabil Benamar
Moulay Ismail University
Morocco

Phone: +212670832236
Email: benamar73@gmail.com
Jerome Haerri
Eurecom
Sophia-Antipolis 06904
France

Phone: +33493008134
Email: Jerome.Haerri@eurecom.fr

Christian Huitema
Private Octopus Inc.
Friday Harbor, WA 98250
U.S.A.

Email: huitema@huitema.net

Jong-Hyouk Lee
Sangmyung University
31, Sangmyeongdae-gil, Dongnam-gu
Cheonan 31066
Republic of Korea

Email: jonghyouk@smu.ac.kr

Thierry Ernst
YoGoKo
France

Email: thierry.ernst@yogoko.fr

Tony Li
Peloton Technology
1060 La Avenida St.
Mountain View, California 94043
United States

Phone: +16503957356
Email: tony.li@tony.li