draft-ietf-roll-home-routing-reqs-00.txt   draft-ietf-roll-home-routing-reqs-01.txt 
Networking Working Group A. Brandt Networking Working Group A. Brandt
Internet Draft Zensys, Inc. Internet Draft Zensys, Inc.
Intended status: Informational G. Porcu Intended status: Informational G. Porcu
Expires: November 2008 Telecom Italia Expires: January 2009 Telecom Italia
May 21, 2008 July 4, 2008
Home Automation Routing Requirement in Low Power and Lossy Networks Home Automation Routing Requirement in Low Power and Lossy Networks
draft-ietf-roll-home-routing-reqs-00 draft-ietf-roll-home-routing-reqs-01
Status of this Memo Status of this Memo
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aware have been or will be disclosed, and any of which he or she aware have been or will be disclosed, and any of which he or she
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BCP 79. BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on November 21, 2008. This Internet-Draft will expire on January 4, 2009.
Copyright Notice Copyright Notice
Copyright (C) The IETF Trust (2008). Copyright (C) The IETF Trust (2008).
Abstract Abstract
This document presents home control and automation application This document presents home control and automation application
specific requirements for ROuting in Low power and Lossy networks specific requirements for ROuting in Low power and Lossy networks
(ROLL). In a modern home, a high number of wireless devices are used (ROLL). In a modern home, a high number of wireless devices are used
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document are to be interpreted as described in RFC-2119 [RFC2119]. document are to be interpreted as described in RFC-2119 [RFC2119].
Table of Contents Table of Contents
1. Terminology....................................................3 1. Terminology....................................................3
2. Introduction...................................................3 2. Introduction...................................................3
3. Home automation applications...................................4 3. Home automation applications...................................4
3.1. Turning off the house when leaving........................4 3.1. Turning off the house when leaving........................4
3.2. Energy conservation and optimizing energy consumption.....5 3.2. Energy conservation and optimizing energy consumption.....5
3.3. Moving a remote control around............................5 3.3. Moving a remote control around............................5
3.4. Adding a new lamp module to the system....................5 3.4. Adding a new lamp module to the system....................6
3.5. Controlling battery operated window shades................6 3.5. Controlling battery operated window shades................6
3.6. Remote video surveillance.................................6 3.6. Remote video surveillance.................................6
3.7. Healthcare................................................6 3.7. Healthcare................................................6
3.7.1. At-home health reporting.............................7 3.7.1. At-home health reporting.............................7
3.7.2. At-home health monitoring............................7 3.7.2. At-home health monitoring............................7
3.7.3. Healthcare routing considerations....................8 3.7.3. Healthcare routing considerations....................8
3.8. Alarm systems.............................................8 3.8. Alarm systems.............................................8
3.9. Battery-powered devices...................................8 3.9. Battery-powered devices...................................9
4. Unique requirements of home automation applications............9 4. Unique requirements of home automation applications............9
4.1. Support of groupcast......................................9 4.1. Support of groupcast......................................9
4.2. Metric-based Routing......................................9 4.2. Constraint-based Routing..................................9
4.3. Support of Mobility......................................10 4.3. Support of Mobility......................................10
4.4. Support of periodical scanning...........................10 4.4. Support of Periodical Scanning...........................10
4.5. Scalability..............................................10 4.5. Scalability..............................................11
4.6. Convergence Time.........................................11 4.6. Convergence Time.........................................11
4.7. Manageability............................................11 4.7. Manageability............................................11
5. Traffic pattern...............................................11 5. Traffic Pattern...............................................11
6. Open issues...................................................11 6. Open issues...................................................12
7. Security Considerations.......................................12 7. Security Considerations.......................................12
8. IANA Considerations...........................................12 8. IANA Considerations...........................................13
9. Acknowledgments...............................................12 9. Acknowledgments...............................................13
10. References...................................................12 10. References...................................................13
10.1. Normative References....................................12 10.1. Normative References....................................13
10.2. Informative References..................................12 10.2. Informative References..................................14
Author's Addresses...............................................13 Disclaimer of Validity...........................................15
Intellectual Property Statement..................................13
Disclaimer of Validity...........................................13
1. Terminology 1. Terminology
ROLL: ROuting in Low-power and Lossy networks ROLL: ROuting in Low-power and Lossy networks
ROLL device: A ROLL network node with constrained CPU and memory
resources; potentially constrained power resources.
Access Point: The access point is an infrastructure device that Access Point: The access point is an infrastructure device that
connects the low power and lossy network system to the connects the low power and lossy network system to the
Internet, possibly via a customer premises local area Internet, possibly via a customer premises local area
network (LAN). network (LAN).
LAN: Local Area Network. LAN: Local Area Network.
PAN: Personal Area Network. PAN: Personal Area Network.
A geographically limited wireless network based on A geographically limited wireless network based on
e.g. 802.15.4 or Z-Wave radio. e.g. 802.15.4 or Z-Wave radio.
Channel: RF frequency band used to transmit a modulated signal Channel: Radio frequency band used to transmit a modulated
carrying packets. signal carrying packets.
Downstream: Data direction traveling from a LAN to a PAN device. Downstream: Data direction traveling from a Local Area Network
(LAN) to a Personal Area Network (PAN) device.
Upstream: Data direction traveling from a PAN to a LAN device. Upstream: Data direction traveling from a PAN to a LAN device.
RF: Radio Frequency.
Sensor: A PAN device that measures data and/or detects an Sensor: A PAN device that measures data and/or detects an
event. event.
HA: Home Automation.
2. Introduction 2. Introduction
This document presents the home control and automation application This document presents the home control and automation application
specific requirements for Routing in Low power and Lossy Networks specific requirements for Routing in Low power and Lossy Networks
(ROLL). In a modern home, a high number of wireless devices are used (ROLL). In a modern home, a high number of wireless devices are used
for a wide set of purposes. Examples include lighting control for a wide set of purposes. Examples include lighting control
modules, heating control panels, light sensors, temperature sensors, modules, heating control panels, light sensors, temperature sensors,
gas/water leak detectors, motion detectors, video surveillance, gas/water leak detectors, motion detectors, video surveillance,
healthcare systems and advanced remote controls. Basic home control healthcare systems and advanced remote controls. Basic home control
modules such as wall switches and plug-in modules may be turned into modules such as wall switches and plug-in modules may be turned into
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puts a limit to the physical size of the battery; and thus, the puts a limit to the physical size of the battery; and thus, the
battery capacity. As a result, it is common for low-power sensor- battery capacity. As a result, it is common for low-power sensor-
style nodes to shut down radio and CPU resources for most of the style nodes to shut down radio and CPU resources for most of the
time. Often, the radio uses the same power for listening as for time. Often, the radio uses the same power for listening as for
transmitting. transmitting.
Section 3. describes a few typical use cases for home automation Section 3. describes a few typical use cases for home automation
applications. Section 4. discusses the routing requirements for applications. Section 4. discusses the routing requirements for
networks comprising such constrained devices in a home network networks comprising such constrained devices in a home network
environment. These requirements may be overlapping requirements environment. These requirements may be overlapping requirements
derived from other application-specific requirements documents or as derived from other application-specific requirements.
listed in [I-D.culler-roll-routing-reqs].
3. Home automation applications 3. Home automation applications
Home automation applications represent a special segment of networked Home automation applications represent a special segment of networked
wireless devices with its unique set of requirements. To facilitate wireless devices with its unique set of requirements. To facilitate
the requirements discussion in Section 4, this section lists a few the requirements discussion in Section 4, this section lists a few
typical use cases of home automation applications. New applications typical use cases of home automation applications. New applications
are being developed at a high pace and this section does not mean to are being developed at a high pace and this section does not mean to
be exhaustive. Most home automation applications tend to be running be exhaustive. Most home automation applications tend to be running
some kind of command/response protocol. The command may come from some kind of command/response protocol. The command may come from
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happen at the same time. A well-known problem in wireless home happen at the same time. A well-known problem in wireless home
automation is the "popcorn effect": Lamps are turned on one at a automation is the "popcorn effect": Lamps are turned on one at a
time, at a rate so slow that it is clearly visible. Some existing time, at a rate so slow that it is clearly visible. Some existing
home automation solutions use a clever mix of a "subnet groupcast" home automation solutions use a clever mix of a "subnet groupcast"
message with no acknowledgement and no forwarding before sending message with no acknowledgement and no forwarding before sending
acknowledged singlecast messages to each lighting device. acknowledged singlecast messages to each lighting device.
The controller forms the groups and decides which nodes should The controller forms the groups and decides which nodes should
receive "turn-off" or "turn-on" requests. receive "turn-off" or "turn-on" requests.
Thus, a solution is needed for addressing groups of nodes without
prior management of group membership in the receiving nodes.
3.2. Energy conservation and optimizing energy consumption 3.2. Energy conservation and optimizing energy consumption
Parts of the world using air conditioning may let shades go down and Parts of the world using air conditioning may let shades go down and
turn off the AC device when leaving home. Air conditioning may start turn off the AC device when leaving home. Air conditioning may start
by timer or via motion sensor when the owner returns home. The owner by timer or via motion sensor when the owner returns home. The owner
may even activate the air conditioning via cell phone before getting may even activate the air conditioning via cell phone before getting
home. home.
Geographical areas using central heating may turn off heating when Geographical areas using central heating may turn off heating when
not at home and use a reduced temperature during night time. not at home and use a reduced temperature during night time.
The power grid may experience periods where more wind-generated power The power grid may experience periods where more wind-generated power
is produced than is needed. Typically this may happen during night is produced than is needed. Typically this may happen during night
hours. The washing machine and dish washer may just as well work hours. The washing machine and dish washer may just as well work
while power is cheap. The electric car should also charge its while power is cheap. The electric car should also charge its
batteries on cheap power. batteries on cheap power.
Most of these applications are mains powered and may thus provide In periods where electricity demands exceed available supply,
reliable routing resources. appliances such as air conditioning, climate control systems, washing
machines etc. can be turned off to avoid overloading the power grid.
Wireless remote control of the household appliances is well-suited
for this application. The start/stop decision for the appliances can
be regulated by dynamic power pricing information obtained from the
electricity utility companies.
Most of these applications are mains powered and are thus ideal for
providing reliable, always-on routing resources. Battery-powered
nodes, by comparison, are constrained routing resources and may only
provide reliable routing under some circumstances.
3.3. Moving a remote control around 3.3. Moving a remote control around
A remote control is a typical example of a mobile device in a home A remote control is a typical example of a mobile device in a home
automation network. An advanced remote control may be used for automation network. An advanced remote control may be used for
dimming the light in the dining room while eating and later on, dimming the light in the dining room while eating and later on,
turning up the music while doing the dishes in the kitchen. Reaction turning up the music while doing the dishes in the kitchen. Reaction
must appear to be instant (within a few hundred milliseconds) even must appear to be instant (within a few hundred milliseconds) even
when the remote control has moved to a new location. The remote when the remote control has moved to a new location. The remote
control may be communicating to either a central home automation control may be communicating to either a central home automation
controller or directly to the lamps and the media center. controller or directly to the lamps and the media center.
3.4. Adding a new lamp module to the system 3.4. Adding a new lamp module to the system
Small-size, low-cost modules may have no user interface except for a Small-size, low-cost modules may have no user interface except for a
single button. Thus, an automated inclusion process is needed for single button. Thus, an automated inclusion process is needed for
controllers to find new modules. Inclusion covers the detection of controllers to find new modules. Inclusion covers the detection of
neighbors and assignment of a unique node ID. Inclusion should be neighbors and assignment of a unique node ID. Inclusion should be
completed within a few seconds. completed within a few seconds.
Distribution of unique addresses is usually performed by a central
controller. In this case, it must be possible to route the inclusion
request from the joining node to the central controller even before
the joining node is assigned a unique address.
3.5. Controlling battery operated window shades 3.5. Controlling battery operated window shades
In consumer premises, window shades are often battery-powered as In consumer premises, window shades are often battery-powered as
there is no access to mains power over the windows. For battery there is no access to mains power over the windows. For battery
conservation purposes, the receiver is sleeping most of the time. A conservation purposes, the receiver is sleeping most of the time. A
home automation controller sending commands to window shades via ROLL home automation controller sending commands to window shades via ROLL
resources will have no problems delivering the packet to the router, devices will have no problems delivering the packet to the router,
but the router will have to wait for some time before the command can but the router may have to wait for some time before the command can
be delivered to the window shades; e.g. up to 250ms. be delivered to the window shades if the receiver is sleeping; e.g.
up to 250ms.
3.6. Remote video surveillance 3.6. Remote video surveillance
Remote video surveillance is a fairly classic application for Home Remote video surveillance is a fairly classic application for Home
networking providing the ability for the end user to get a video networking providing the ability for the end user to get a video
stream from a Web Cam reached via the Internet, which can be stream from a Web Cam reached via the Internet, which can be
triggered by the end-user that has received an alarm from a movement triggered by the end-user that has received an alarm from a movement
sensor or smoke detector - or the user simply wants to check the home sensor or smoke detector - or the user simply wants to check the home
status via video. status via video.
Note that in the former case, more than likely, there will be a form Note that in the former case, more than likely, there will be a form
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Applications might include: Applications might include:
o Temperature o Temperature
o Weight o Weight
o Blood pressure o Blood pressure
o Insulin level o Insulin level
o ECG
o Electrocardiogram (ECG)
o Position tracker o Position tracker
3.7.3. Healthcare routing considerations 3.7.3. Healthcare routing considerations
From a ROLL perspective, all the above-mentioned applications may run From a ROLL perspective, all the above-mentioned applications may run
on battery. They may also be portable and therefore need to locate a on battery. They may also be portable and therefore need to locate a
new neighbor router on a frequent basis. new neighbor router on a frequent basis.
Not being powered most of the time, the nodes should not be used as Not being powered most of the time, the nodes should not be used as
routing nodes. However, sleeping, battery-powered nodes may be routing nodes. However, sleeping, battery-powered nodes may be
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most of them, most of the time, have prevention and monitoring most of them, most of the time, have prevention and monitoring
activity in which routing requirements are deterministic, but all of activity in which routing requirements are deterministic, but all of
them have an alarm state in which nodes may burst an aperiodic alarm. them have an alarm state in which nodes may burst an aperiodic alarm.
3.9. Battery-powered devices 3.9. Battery-powered devices
For convenience and low operational costs, power consumption of For convenience and low operational costs, power consumption of
consumer products must be kept at a very low level to achieve a long consumer products must be kept at a very low level to achieve a long
battery lifetime. One implication of this fact is that RAM memory is battery lifetime. One implication of this fact is that RAM memory is
limited and it may even be powered down; leaving only a few 100 bytes limited and it may even be powered down; leaving only a few 100 bytes
alive during the sleep phase. of RAM alive during the sleep phase.
4. Unique requirements of home automation applications 4. Unique requirements of home automation applications
Home automation applications have a number of specific requirements Home automation applications have a number of specific requirements
related to the set of home networking applications and the perceived related to the set of home networking applications and the perceived
operation of the system. operation of the system.
4.1. Support of groupcast 4.1. Support of groupcast
The routing protocol must provide the ability to route a packet Groupcast, in the context of home automation, is defined as the
towards a single device (unicast), a set of devices (also referred to ability to simultaneously transmit a message to a group of recipients
as "groupcast" in this document) or all devices (broadcast) in the without prior interaction with the group members (i.e. group setup).
house. A use-case for groupcast is given in Section 3.1.
Broadcast and groupcast in home automation MAY be used to deliver the
illusion that all recipients respond simultaneously. Distant
recipients out of direct range may not react to the (unacknowledged)
groupcast. Acknowledged unicast delivery MUST be used subsequently.
The support of unicast, groupcast and broadcast also has an The support of unicast, groupcast and broadcast also has an
implication on the addressing scheme and are outside the scope of implication on the addressing scheme and are outside the scope of
this document that focuses on the routing requirements aspects. this document that focuses on the routing requirements aspects.
It MUST be to possible to address a group of receivers known by the It MUST be to possible to address a group of receivers known by the
sender even if the receivers do not know that they have been grouped sender even if the receivers do not know that they have been grouped
by the sender. by the sender.
Alternatively, a companion specification SHOULD define how to 4.2. Constraint-based Routing
indirectly address a group of nodes on the application layer via
classic broadcast in the network layer; e.g. by use of a bitmap in a
header extension.
4.2. Metric-based Routing
[ABR NOTE: IETF-71 WG meeting indicated that the term "constrained"
has a very specific meaning in the routing community inside IETF.
What I understood was that the draft should be using the term
"metric-based routing"]
Simple battery-powered nodes such as movement sensors on garage doors Simple battery-powered nodes such as movement sensors on garage doors
and rain meters may not be able to assist in routing. Depending on and rain meters may not be able to assist in routing. Depending on
the node type, the node never listens at all, listens rarely or makes the node type, the node never listens at all, listens rarely or makes
contact on demand to a pre-configured target node. Attempting to contact on demand to a pre-configured target node. Attempting to
communicate to such nodes may require long time before getting a communicate to such nodes may require long time before getting a
response. response.
Other battery-powered nodes may have the capability to participate in Other battery-powered nodes may have the capability to participate in
routing. The routing protocol should either share the load between routing. The routing protocol should either share the load between
nodes to preserve battery or only route via mains-powered nodes if nodes to preserve battery or only route via mains-powered nodes if
possible. The most reliable routing resource may be a battery-backed, possible. The most reliable routing resource may be a battery-backed,
mains-powered smoke alarm. mains-powered smoke alarm.
The routing protocol MUST support metric-based routing taking into The routing protocol MUST support constraint-based routing taking
account node properties (CPU, memory, level of energy, sleep into account node properties (CPU, memory, level of energy, sleep
intervals, safety/convenience of changing battery). intervals, safety/convenience of changing battery).
4.3. Support of Mobility 4.3. Support of Mobility
In a home environment, although the majority of devices are fixed In a home environment, although the majority of devices are fixed
devices, there is still a variety of mobile devices: for example a devices, there is still a variety of mobile devices: for example a
multi-purpose remote control is likely to move. Another example of multi-purpose remote control is likely to move. Another example of
mobile devices is wearable healthcare devices. mobile devices is wearable healthcare devices.
While healthcare devices delivering measurement results can tolerate While healthcare devices delivering measurement results can tolerate
route discovery times measured in seconds, a remote control appears route discovery times measured in seconds, a remote control appears
unresponsive if using more than 0.5 seconds to e.g. pause the music. unresponsive if using more than 0.5 seconds to e.g. pause the music.
While, in theory, all battery-powered devices and mains-powered plug- While, in theory, all battery-powered devices and mains-powered plug-
in modules may be moved, the predominant case is that the sending in modules may be moved, the predominant case is that the sending
node has moved while the rest of the network has not changed. node has moved while the rest of the network has not changed.
The routing protocol MUST provide mobility with convergence time The routing protocol MUST provide mobility with convergence time
below 0.5 second if only the sender has moved. below 0.5 second if only the sender has moved.
The routing protocol SHOULD make use of the fact that if not being A non-responsive node can either be caused by 1) a failure in the
able to deliver a packet, it is most likely that the sending node node, 2) a failed link on the path to the node or 3) a moved node. In
moved; rather than the rest of the network. the first two cases, the node can be expected to reappear at roughly
the same location in the network, whereas it can return anywhere in
the network in the latter case. The search strategy in the routing
protocol will behave differently depending on this expectation. The
routing protocol SHOULD make use of the fact that if not being able
to deliver a packet, it is most likely that the sending node moved;
rather than a failure occurred in that node or in a link on the path
towards it.
4.4. Support of periodical scanning 4.4. Support of Periodical Scanning
The routing protocol MUST support the recognition of neighbors and The routing protocol MUST support the recognition of neighbors and
periodical scanning. This process SHOULD preserve energy capacity as periodical scanning. This process SHOULD preserve energy capacity as
much as possible. much as possible.
(Derived from use case 3.8. Alarm Systems) (Derived from use case 3.8. Alarm Systems)
4.5. Scalability 4.5. Scalability
Looking at the number of wall switches, power outlets, sensors of Looking at the number of wall switches, power outlets, sensors of
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quite realistic that hundreds of low power devices may form a home quite realistic that hundreds of low power devices may form a home
automation network in a fully populated "smart" home. Moving towards automation network in a fully populated "smart" home. Moving towards
professional building automation, the number of such devices may be professional building automation, the number of such devices may be
in the order of several thousands. in the order of several thousands.
Thus, the routing protocol MUST support 250 devices in a subnet. Thus, the routing protocol MUST support 250 devices in a subnet.
The routing protocol SHOULD support 2500 devices in a subnet. The routing protocol SHOULD support 2500 devices in a subnet.
4.6. Convergence Time 4.6. Convergence Time
A home automation PAN is subject to various instability due to signal A home automation Personal Area Network (PAN) is subject to various
strength variation, moving persons and the like. Furthermore, as the instability due to signal strength variation, moving persons and the
number of devices increases, the probability of a node failure also like. Furthermore, as the number of devices increases, the
increases. probability of a node failure also increases.
Measured from the transmission of a packet, the following convergence Measured from the transmission of a packet, the following convergence
time requirements apply. time requirements apply.
The routing protocol MUST converge within 0.5 second if no nodes have The routing protocol MUST converge within 0.5 second if no nodes have
moved. moved.
The routing protocol MUST converge within 2 seconds if the The routing protocol MUST converge within 2 seconds if the
destination node of the packet has moved. destination node of the packet has moved.
4.7. Manageability 4.7. Manageability
The ability of the home network to support auto-configuration is of The ability of the home network to support auto-configuration is of
the utmost importance. Indeed, most end users will not have the the utmost importance. Indeed, most end users will not have the
expertise and the skills to perform advanced configuration and expertise and the skills to perform advanced configuration and
troubleshooting. Thus the routing protocol designed for home PAN MUST troubleshooting. Thus the routing protocol designed for home PAN MUST
provide a set of features including 0 configuration of the routing provide a set of features including zero-configuration of the routing
protocol for a new node to be added to the network. protocol for a new node to be added to the network. From ROLL
perspective, zero-configuration means that a node can obtain an
address and join the network on its own, without human intervention.
Furthermore, a failing node MUST NOT have a global impact on the The routing protocol MUST support the ability to isolate a
routing protocol. The routing protocol SHOULD support the ability to misbehaving node thus preserving the correct operation of overall
isolate a misbehaving node thus preserving the correct operation of network.
overall network.
5. Traffic pattern 5. Traffic Pattern
Depending on the philosophy of the home network, wall switches may be Depending on the philosophy of the home network, wall switches may be
configured to directly control individual lamps or alternatively, all configured to directly control individual lamps or alternatively, all
wall switches send control commands to a central lighting control wall switches send control commands to a central lighting control
computer which again sends out control commands to relevant devices. computer which again sends out control commands to relevant devices.
In a distributed system, the traffic tends to be any-to-many. In a In a distributed system, the traffic tends to be any-to-many. In a
centralized system, it is a mix of any-to-one and one-to-many. centralized system, it is a mix of any-to-one and one-to-many.
Wall switches only generate traffic when activated, which typically
happens from a one to tens of times per hour.
Remote controls have a similar transmit pattern to wall switches, but
are activated more frequently.
Temperature/air pressure/rain sensors send frames when queried by the
user or can be preconfigured to send measurements at fixed intervals
(typically minutes). Motion sensors typically send a frame when
motion is first detected and another frame when an idle period with
no movement has elapsed. The highest transmission frequency depends
on the idle period used in the sensor. Sometimes, a timer will
trigger a frame transmission when an extended period without status
change has elapsed.
All frames sent in the above examples are quite short, typically less
than 5 bytes of payload. Lost frames and interference from other
transmitters may lead to retransmissions. In all cases,
acknowledgment frames with a size of a few bytes are used.
6. Open issues 6. Open issues
Other items to be addressed in further revisions of this document Other items to be addressed in further revisions of this document
include: include:
o Load Balancing (Symmetrical and Asymmetrical) o Load Balancing (Symmetrical and Asymmetrical)
o Security o Security
7. Security Considerations 7. Security Considerations
TBD Encryption can be employed to provide confidentiality, integrity and
authentication of the messages carried on the wireless links. Adding
these capabilities to the ROLL devices will degrade energy efficiency
and increase cost, so a trade-off must be made for each specific
application.
Door locks, alarm sensors and medication dosage equipment are
examples where strong encryption and authentication are needed. The
command to unlock a door must be authenticated, as must the
communication between an alarm sensor and the central alarm
controller. Furthermore, traffic analysis of the alarm system
communication must not reveal if the alarm is activated.
Light dimmers, window shades, motion sensors, weight sensors etc. may
not need encryption.
Protection against unintentional inclusion in neighboring networks
must be provided. Providing confidentiality, integrity and
authentication against malicious opponents is optional.
8. IANA Considerations 8. IANA Considerations
This document includes no request to IANA. This document includes no request to IANA.
9. Acknowledgments 9. Acknowledgments
J. P. Vasseur, Jonathan Hui, Eunsook "Eunah" Kim and Mischa Dohler
are gratefully acknowledged for their contributions to this document.
This document was prepared using 2-Word-v2.0.template.dot. This document was prepared using 2-Word-v2.0.template.dot.
10. References 10. References
10.1. Normative References 10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
10.2. Informative References 10.2. Informative References
[I-D.culler-roll-routing-reqs]
Vasseur, J. and D. Culler, "Routing Requirements for Low
Power And Lossy Networks",
draft-culler-roll-routing-reqs-* (work in progress).
Author's Addresses Author's Addresses
Anders Brandt Anders Brandt
Zensys, Inc. Zensys, Inc.
Emdrupvej 26 Emdrupvej 26
Copenhagen, DK-2100 Copenhagen, DK-2100
Denmark Denmark
Email: abr@zen-sys.com Email: abr@zen-sys.com
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