Internet Engineering Task Force                     Georgios Karagiannis
Internet-Draft                                      University of Twente
Intended status: Experimental                         Anurag Bhargava
Expires: April 12, August 23, 2013                            Cisco Systems, Inc.
                                                       October 12, 2012
                                                       February 23, 2013

        Generic Aggregation of Resource ReSerVation Protocol (RSVP)
              for IPv4 And IPv6 Reservations over PCN domains
                     draft-ietf-tsvwg-rsvp-pcn-03
                     draft-ietf-tsvwg-rsvp-pcn-04

Abstract

   This document specifies the extensions to the Generic Aggregated RSVP
   [RFC4860] for support of the PCN Controlled Load (CL) and Single
   Marking (SM) edge behaviors over a Diffserv cloud using Pre-
   Congestion Notification.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on April 12, August 23, 2013.

Copyright Notice

   Copyright (c) 2012 2013 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   described in the Simplified BSD License.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

Table of Contents
1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
   1.1. Objective   . . . . . . . . . . . . . . . . . . . . . . . . .  4
   1.2. Overview and Motivation . . . . . . . . . . . . . . . . . . .  4
   1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . .  6  7
   1.4. Organization of This Document . . . . . . . . . . . . . . . . 11
2.  Overview of RSVP extensions and Operations . . . . . . . . . . .  10
2.1  11
2.1. Overview of RSVP Aggregation Procedures in PCN domains . . . . .  10
2.1.1 11
2.2. PCN Marking and encoding and transport of pre-congestion
     Information . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.1.2. .  13
2.3. Traffic Classification Within The Aggregation Region . . . .  12
2.1.3. . . 13
2.4. Deaggregator (PCN-egress-node) Determination . . . . . . . .  12
2.1.4. . . 13
2.5. Mapping E2E Reservations Onto Aggregate Reservations . . . .  12
2.1.5. . . 14
2.6  Size of Aggregate Reservations . . . . . . . . . . . . . . .  12
2.1.6. . . 14
2.7. E2E Path ADSPEC update . . . . . . . . . . . . . . . . . . .  13
2.1.7. . . 14
2.8. Intra-domain Routes . . . . . . . . . . . . . . . . . . . . . 13
2.1.8. . .14
2.9.  Inter-domain Routes . . . . . . . . . . . . . . . . . . . . . 13
2.1.9. . 14
2.10. Reservations for Multicast Sessions . . . . . . . . . . . . . 13
2.1.10. . 14
2.11. Multi-level Aggregation . . . . . . . . . . . . . . . . . .  13
2.1.11. . . 15
2.12. Reliability Issues . . . . . . . . . . . . . . . . . . . . . 13
2.1.12. .  15
2.13.  Message Integrity and Node Authentication . . . . . . . . .  13 .  15
3. Elements of Procedure . . . . . . . . . . . . . . . . . . . . . .  13  15
3.1.  Receipt of E2E Path Message By PCN-ingress-node
     (aggregating router) . . . . . . . . . . . . . . . . . . . . . . 13 15
3.2.  Handling Of E2E Path Message By Interior Routers . . . . . . .  14  16
3.3.  Receipt of E2E Path Message By PCN-egress-node
     (deaggregating router) . . . . . . . . . . . . . . . . . . . . . 15 16
3.4.  Initiation of new Aggregate Path Message By PCN-ingress-node
      (Aggregating Router) . . . . . . . . . . . . . . . . . . . . .  15  17
3.5.  Handling Of new Aggregate Path Message By Interior Routers . .  15  17
3.6.  Handling of E2E Resv Message by Deaggregating Router . . . . .  15  17
3.7.  Handling Of E2E Resv Message By Interior Routers . . . . . . .  15  17
3.8. Initiation of New Aggregate Resv Message By Deaggregating Router 15 17
3.9.  Handling of Aggregate Resv Message by Interior Routers . . . .  16  18
3.10.  Handling of E2E Resv Message by Aggregating Router . . . . . . 16 18
3.11.  Handling of Aggregated Resv Message by Aggregating Router . .  16  18
3.12.  Removal of E2E Reservation . . . . . . . . . . . . . . . . . . 17 19
3.13.  Removal of Aggregate Reservation . . . . . . . . . . . . . . . 17 19
3.14.  Handling of Data On Reserved E2E Flow by Aggregating Router .  17  19
3.15.  Procedures for Multicast Sessions . . . . . . . . . . . . . .  17  19
4.  Protocol Elements . . . . . . . . . . . . . . . . . . . . . . . . 17 19
4.1 PCN object . . . . . . . . . . . . . . . . . . . . . . . . . . .  18  20
5.  Security Considerations . . . . . . . . . . . . . . . . . . . . . 23 25
6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . .  23  25
7.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 23 25
8.  Normative References . . . . . . . . . . . . . . . . . . . . . .  23  25
9.  Informative References . . . . . . . . . . . . . . . . . . . . .  24  26
10.  Authors' Address . . . . . . . . . . . . . . . . . . . . . . . . 25 27
1.  Introduction

   Two main Quality of Service (QoS) architectures have been specified
   by the IETF. These are the Integrated Services (Intserv) [RFC1633]
   architecture and the Differentiated Services (DiffServ) architecture
   ([RFC2475]).

   Intserv provides methods for

1.1 Objective

   Pre-Congestion Notification (PCN) can support the delivery of end-to-end Quality quality of
   Service service
   (QoS) to applications over heterogeneous networks. One of the
   QoS signaling protocols used by the Intserv architecture inelastic flows within a Diffserv domain in a simple,
   scalable, and robust fashion.  Two mechanisms are used: admission
   control and flow termination.  Admission control is the
   Resource reServation Protocol (RSVP) [RFC2205], which can be used by
   applications to request per-flow resources from the network. These
   RSVP requests can be admitted decide
   whether to admit or rejected by block a new flow request, while flow termination
   is used in abnormal circumstances to decide whether to terminate some
   of the existing flows.  To support these two features, the overall
   rate of PCN-traffic is metered on every link in the domain, and PCN-
   packets are appropriately marked when certain configured rates are
   exceeded.  These configured rates are below the rate of the link,
   thus providing notification to boundary nodes about overloads before
   any congestion occurs (hence "pre-congestion" notification).  The
   PCN-egress-nodes measure the rates of differently marked PCN traffic
   in periodic intervals and report these rates to the Decision Points
   for admission control and flow termination; the Decision Points use
   these rates to make decisions.  The Decision Points may be collocated
   with the PCN-ingress-nodes, or their function may be implemented in a
   centralized node. For more details see [RFC5559], [RFC6661], and
   [RFC6662].

   The main objective of this document is to specify the signalling
   protocol that can be used within a Pre-Congestion Notification (PCN)
   domain to carry reports from a PCN-egress-node to a PCN Decision
   point, considering that the PCN decision Point and PCN-ingress-node
   are collocated.
   If the PCN decision point is not collocated with the PCN-ingress-node
   then additional signalling procedures are required that are out of
   the scope of this document.

   Several signaling protocols can be used to carry reports from a PCN-
   egress-node to a PCN-ingress-nodes. However, since both PCN-egress-
   node and PCN-ingress-nodes are located on the data path, a signaling
   protocol that follows the same path as the data path, like RSVP
   (Resource Reservation Protocol), is more suited for this purpose. In
   particular, this document specifies extensions to Generic
   Aggregated RSVP [RFC4860] for support of the PCN Controlled Load (CL)
   and Single Marking (SM) edge behaviors over a Diffserv cloud using
   Pre-Congestion Notification.

1.2 Overview and Motivation

   Two main Quality of Service (QoS) architectures have been specified
   by the IETF. These are the Integrated Services (Intserv) [RFC1633]
   architecture and the Differentiated Services (DiffServ) architecture
   ([RFC2475]).

   Intserv provides methods for the delivery of end-to-end Quality of
   Service (QoS) to applications over heterogeneous networks. One of the
   QoS signaling protocols used by the Intserv architecture is the
   Resource reServation Protocol (RSVP) [RFC2205], which can be used by
   applications to request per-flow resources from the network. These
   RSVP requests can be admitted or rejected by the network.
   Applications can express their quantifiable resource requirements
   using Intserv parameters as defined in [RFC2211] and [RFC2212]. The
   Controlled Load (CL) service [RFC2211] is a quality of service (QoS)
   closely approximating the QoS that the same flow would receive from a
   lightly loaded network element. The CL service is useful for
   inelastic flows such as those used for real-time media.

   The DiffServ architecture can support the differentiated treatment of
   packets in very large scale environments. While Intserv and RSVP
   classify packets per-flow, Diffserv networks classify packets into
   one of a small number of aggregated flows or "classes", based on the
   Diffserv codepoint (DSCP) in the packet IP header. At each Diffserv
   router, packets are subjected to a "per-hop behavior" (PHB), which is
   invoked by the DSCP.  The primary benefit of Diffserv is its
   scalability, since the need for per-flow state and per-flow
   processing, is eliminated.

   However, DiffServ does not include any mechanism for communication
   between applications and the network.  Several solutions have been
   specified to solve this issue. One of these solutions is Intserv over
   Diffserv [RFC2998] including resource-based admission control,
   policy-based admission control, assistance in traffic
   identification/classification, and traffic conditioning.
   Intserv over Diffserv can operate over a statically provisioned
   Diffserv region or RSVP aware. When it is RSVP aware, several
   mechanisms may be used to support dynamic provisioning and topology-
   aware admission control, including aggregate RSVP reservations, per-
   flow RSVP, or a bandwidth broker.
   [RFC3175] specifies aggregation of Resource ReSerVation
   Protocol (RSVP) end-to-end reservations over aggregate RSVP
   reservations. In [RFC3175] the RSVP aggregated reservation is
   characterized by a RSVP SESSION object using the 3-tuple <source IP
   address, destination IP address, Diffserv Code Point>.

   Several scenarios require the use of multiple generic aggregate
   reservations that are established for a given PHB from a given source
   IP address to a given destination IP address, see [RFC4860],
   [SIG-NESTED]. [SIG-NESTED],
   [RFC4860]. For example, multiple generic aggregate reservations
   can be applied in the situation that multiple e2e reservations using
   different preemption priorities need to be aggregated through a PCN-
   domain using the same PHB. By using multiple aggregate reservations
   for the same PHB allows enforcement of the different preemption
   priorities within the aggregation region. This allows more efficient
   management of the Diffserv resources, and in periods of resource
   shortage, this allows sustainment of a larger number of E2E
   reservations with higher preemption priorities. In particular,
   [SIG-NESTED] discusses in detail how end-to-end RSVP reservations can
   be established in a nested VPN environment through RSVP aggregation.

   [RFC4860] provides generic aggregate reservations by extending
   [RFC3175] to support multiple aggregate reservations for the same
   source IP address, destination IP address, and PHB (or set of PHBs).
   In particular, multiple such generic aggregate reservations can be
   established for a given PHB from a given source IP address to a given
   destination IP address. This is achieved by adding the concept of a
   Virtual Destination Port and of an Extended Virtual Destination Port
   in the RSVP SESSION object. In addition to this, the RSVP SESSION
   object for generic aggregate reservations uses the PHB Identification
   Code (PHB-ID) defined in [RFC3140], instead of using the Diffserv
   Code Point (DSCP) used in [RFC3175]. The PHB-ID is used to identify
   the PHB, or set of PHBs, from which the Diffserv resources are to be
   reserved.

   The main objective of Pre-Congestion Notification (PCN) is RSVP like signaling protocol required to support
   the quality of service (QoS) of inelastic flows within carry reports from a Diffserv
   domain in
   PCN-egress-node to a simple, scalable, and robust fashion. Two mechanisms are
   used: admission control, PCN-ingress-node needs to decide whether follow the PCN
   signaling requirements defined in [RFC6663]. In addition to admit or block a new
   flow request,
   that the signalling protocol functionality supported by the PCN-
   ingress-nodes and (in abnormal circumstances) flow termination PCN-egress-nodes needs to maintain logical
   aggregate constructs (i.e. ingress-egrees-aggregate state) and be
   able to map e2e reservations to these aggregate constructs. Moreover,
   no actual reservation state is needed to be maintained inside the PCN
   domain, i.e., the PCN-interior-nodes are not maintaing any
   reservation state.

   This can be accomplished by two possible approaches:

   Approach (1):

     o) adapting the RFC 4860 aggregation procedures to fit the PCN
        requirements with as little change as possible over the RFC 4860
        functionality

     o) hence performing aggregate RSVP signaling (even if it is to
   decide whether be
        ignored by PCN interior nodes)

     o) using this aggregate RSVP signaling procedures to carry PCN
        information from PCN-egress-node to terminate some of the existing flows. To achieve
   this, PCN-ingress-node.

   Approach (2):

     o) adapting the overall rate of PCN-traffic is metered on every link in RFC 4860 aggregation procedures to fit the
   PCN-domain, and PCN-packets are appropriately marked when certain
   configured rates are exceeded.  These configured rates are below PCN
        requirements with more significant changes over RFC4860 (i.e.
        the
   rate aspect of the link thus providing notification procedures that have to PCN-boundary-nodes
   about incipient overloads before any congestion occurs (hence do with maintaining
        aggregate states and to do with mapping the
   "pre" part of "pre-congestion notification"). The level of marking
   allows decisions e2e reservations to be made about whether
        aggregate constructs are kept, but the procedures that have to admit or terminate PCN-
   flows.

   The PCN-egress-nodes measure
        do with the rates of differently marked
   PCN-traffic in periodic intervals aggregate RSVP signaling and report these rates to aggregate reservation
        establishment/maintenance are dropped).

     o) hence not performing aggregate RSVP signaling

     o) piggy-backing of the
   decision points for admission control PCN information inside the e2e RSVP
        signaling.

   Both approaches are probably viable, however, since the RFC 4860
   operations have been thoroughly studied and flow termination, based on
   which they take their decisions. The decision points may implemented, it can be
   collocated
   considered that the RFC 4860 solution can better deal with the PCN-ingress-nodes or their function may be
   implemented more
   challenging situations (rerouting in the PCN domain, failure of an
   PCN-ingress-node, failure of an PCN-egress-node, rerouting towards a centralized node. For more details see [RFC5559],
   [RFC6661], [RFC6662]. In this document it
   different edge, etc.). This is considered that also the
   decision point is collocated with reason of chossing Approach
   (1) for the specification of the signaling protocol used to carry PCN
   information from the PCN-egress-node to the PCN-ingress-node. In
   particular, this document specifies extensions to Generic
   Aggregated RSVP [RFC4860] for support of the PCN Controlled Load (CL)
   and Single Marking (SM) edge behaviors over a Diffserv cloud using
   Pre-Congestion Notification.

   This document follows the PCN signaling requirements defined in
   [RFC6663] and specifies the extensions to the Generic Aggregated RSVP
   [RFC4860] for the support of PCN edge behaviors as specified in
   [RFC6661] and [RFC6662]. Moreover, this document specifies how RSVP
   aggregation can be used to setup and maintain: (1) Ingress Egress
   Aggregate (IEA) states at Ingress and Egress nodes and (2) generic
   aggregation of RSVP end-to-
   end end-to-end RSVP reservations over PCN (Congestion
   and Pre-Congestion Notification) domains.

   This document, and according to [RFC4860] MAY also be used end-to-end
   directly by end-systems attached to a Diffserv network.
   Furthermore, this document and according to [RFC4860], in absence of
   e2e RSVP flows, a variety of policies (not defined in this document)
   can be used at the Aggregator to set the DSCP of packets passing into
   the aggregation region and how they are mapped onto generic aggregate
   reservations. These policies are not described in this document but
   are a matter of local configuration.

   In

   To comply with this document it is considered that the specification, PCN-nodes MUST be able to
   support the functionality specified in [RFC5670], [RFC5559],
   [RFC6660], [RFC6661], [RFC6662]. Furthermore, the PCN-boundary-nodes
   MUST support the RSVP generic aggregated reservation procedures
   specified in [RFC4860] which are augmented with procedures specified
   in this document.

1.1.

1.3.  Terminology

   This document uses terms defined in [RFC4860], [RFC3175], [RFC5559],
   [RFC5670], [RFC6661], [RFC6662].

   For readability, a number of definitions from [RFC3175] as well as
   definitions for terms used in [RFC5559], [RFC6661], and [RFC6662] are
   provided here, where some of them are augmented with new meanings:

   Aggregator       This is the process in (or associated with) the
                    router at the ingress edge of the aggregation region
                    (with respect to the end-to-end RSVP reservation)
                    and behaving in accordance with [RFC4860].  In this
                    document, it is also the PCN-ingress-node and the
                    decision point.

   Deaggregator     This is the process in (or associated with) the
                    router at the egress edge of the aggregation region
                    (with respect to the end-to-end RSVP reservation)
                    and behaving in accordance with [RFC4860].  In this
                    document, it is also the PCN-egress-node.

   E2E (or e2e)     end to end

   E2E Reservation  This is an RSVP reservation such that:

                    (i)   corresponding RSVP Path messages are initiated
                          upstream of the Aggregator and terminated
                          downstream of the Deaggregator, and

                    (ii)  corresponding RSVP Resv messages are initiated
                          downstream of the Deaggregator and terminated
                          upstream of the Aggregator, and

                    (iii) this RSVP reservation is aggregated over an
                          Ingress Egress Aggregate (IEA) between the
                          Aggregator and Deaggregator.
                    An E2E RSVP reservation may be a per-flow
                    reservation, which in this document is only
                    maintained at the PCN-ingress-node and PCN-egress-
                    node. Alternatively, the E2E reservation may itself
                    be an aggregate reservation of various types (e.g.,
                    Aggregate IP reservation, Aggregate IPsec
                    reservation, see [RFC4860]).  As per regular RSVP
                    operations, E2E RSVP  reservations are
                    unidirectional.

   PHB-ID (Per Hop Behavior Identification Code)
                     A 16-bit field containing the Per Hop Behavior
                     Identification Code of the PHB, or of the set of
                     PHBs, from which Diffserv resources
                     are to be reserved.  This field MUST be encoded as
                     specified in Section 2 of [RFC3140].

   VDstPort (Virtual Destination Port)

                     A 16-bit identifier used in the SESSION that
                     remains constant over the life of the generic
                     aggregate reservation.

   Extended vDstPort (Extended Virtual Destination Port)

                     An identifier used in the SESSION that remains
                     constant over the life of the generic aggregate
                     reservation. The length of this idenitifier is 32-
                     bits when IPv4 addresses are used and 128 bits when
                     IPv6 addresses are used. A sender(or Aggregator)
                     that wishes to narrow the scope of a SESSION to the
                     sender-receiver pair (or Aggregator-Deaggregator
                     pair) SHOULD place its IPv4 or IPv6 address here as
                     a network unique identifier. A sender (or
                     Aggregator) that wishes to use a common session
                     with other senders (or Aggregators) in order to use
                     a shared reservation across senders (or
                     Aggregators) MUST set this field to all zeros.

                     In this document, the Extended vDstPort SHOULD
                     contain the IPv4 or IPv6 address of the Aggregator.

   PCN-domain:      a PCN-capable domain; a contiguous set of
                    PCN-enabled nodes that perform Diffserv scheduling
                    [RFC2474]; the complete set of PCN-nodes that in
                    principle can, through PCN-marking packets,
                    influence decisions about flow admission and
                    termination for the PCN-domain; includes
                    the PCN-egress-nodes, which measure these
                    PCN-marks, and the PCN-ingress-nodes.

   PCN-boundary-node: a PCN-node that connects one PCN-domain to a node
                    either in another PCN-domain or in a non-PCN-domain.

   PCN-interior-node: a node in a PCN-domain that is not a PCN-
                    boundary-node.

   PCN-node:        a PCN-boundary-node or a PCN-interior-node.

   PCN-egress-node: a PCN-boundary-node in its role in handling
                    traffic as it leaves a PCN-domain.

   PCN-ingress-node: a PCN-boundary-node in its role in handling
                    traffic as it enters a PCN-domain. In this
                    document the PCN-ingress-node operates also as a
                    Decision Point and aggregator.

   PCN-traffic,
   PCN-packets,
   PCN-BA:          a PCN-domain carries traffic of different Diffserv
                    behavior aggregates (BAs) [RFC2474]. The PCN-BA
                    uses the PCN mechanisms to carry PCN-traffic, and
                    the corresponding packets are PCN-packets.
                    The same network will carry traffic of other
                    Diffserv BAs.  The PCN-BA is
                    distinguished by a combination of the Diffserv
                    codepoint (DSCP) and ECN fields.

   Microflow:       a single instance of an application-to-application
 (from [RFC2474])   flow of packets which is identified by source
                    address, destination address, protocol id, and
                    source port, destination port (where applicable).

  e2e microflow     a microflow where its associated packets are being
                    forwarded on an E2E path.

   PCN-flow:        the unit of PCN-traffic that the PCN-boundary-node
                    admits (or terminates); the unit could be a single
                    e2e microflow (as defined in [RFC2474]) or some
                    identifiable collection of microflows.

RSVP generic aggregated reservation: an RSVP reservation that is
                    identified by using the RSVP SESSION object
                    for generic RSVP aggregate reservation. This RSVP
                    SESSION object is based on the RSVP SESSION object
                    specified in [RFC4860] augmented with the following
                    information:
                    o) the IPv4 DestAddress, IPv6 DestAddress SHOULD be
                       set to the IPv4 or IPv6 destination addresses,
                       respectively, of the Deaggregator (PCN-egress-
                       node)

                    o) PHB-ID (Per Hop Behavior Identification Code)
                       SHOULD be set equal to PCN-compatible Diffserv
                       codepoint(s).

                    o) Extended vDstPort SHOULD be set to the IPv4 or
                       IPv6 destination addresses, of the Aggregator
                       (PCN-ingress-node)

  Ingress-egress-aggregate (IEA):
                    The collection of PCN-packets from all PCN-flows
                    that travel in one direction between a specific pair
                    of PCN-boundary-nodes. An ingress-
                    egress-aggregate ingress-egress-aggregate
                    is identified by the combination of (1) fields), (2) PCN-BA
                    (i.e.,  combination of the DSCP and ECN fields),(2)
                    IP addresses of the specific pair of
                    PCN-boundary-nodes used by a the
                    ingress-egress-aggregate. In this document one RSVP
                    generic aggregated reservation is mapped to only one
                    ingress-egress-aggregate, while one ingress-egress-
                    aggregate
                    ingress-egress-aggregate is mapped to either one
                    or to more than one RSVP generic aggregated
                    reservations.

   PCN-admission-state

   PCN-admission-state:
                    The state ("admit" or "block") derived by the
                    Decision Point for a given ingress-egress-aggregate
                    based on statistics about PCN-packet marking.  The
                    Decision Point decides to admit or block new flows
                    offered to the aggregate based on the current value
                    of the PCN-admission-state.

   Congestion level estimate (CLE) (CLE):
                    The ratio of PCN-marked to total PCN-traffic
                    (measured in octets) received for a given ingress-
                    egress-aggregate during a given measurement period.
                    The CLE is used to derive the PCN-admission-state
                    and is also used by the report suppression procedure
                    if report suppression is activated.

   t_meas

  t-meas:
                   A configurable time interval that defines the
                   measurement period over which the PCN-egress-node
                   collects statistics relating to PCN-traffic marking.

  t_maxsuppress
                   A configurable time interval after which the
                   PCN-egress-node MUST send a report to the Decision
                   Point for a given ingress-egress-aggregate regardless
                   of the most recent values of the CLE.  This
                   mechanism provides the Decision Point with a periodic
                   confirmation of liveness when report suppression is
                   activated.

   t_fail

  t-fail:
                   An interval after which the Decision Point (i.e.,
                   PCN-ingress-node) concludes
                   That that communication from a
                   given PCN-egress-node has failed if it has received
                   no reports from the PCN-egress-node during that
                   interval.

   t_crit

  t-recvFail:
                   A configurable interval used in the calculation of
                    T_fail.

   t-recvFail

                    An ingress-egress-aggregate timer per ingress-egress-aggregate that is used at
                    The the
                   Decision point (in this document at the PCN-
                    ingress-node) which when expires raises (i.e., PCN-ingress-node) sets every
                   time it receives an alarm to
                    management, and activates RSVP Aggregated RESV message for
                   that ingress-egress-aggregate. When its value
                   reaches t-fail it is assumed that the PCN-ingress-node to
                    block PCN-ingress-
                   node has lost contact with the PCN-egress-node.
                   Therefore the PCN-ingress-node blocks admission of
                   new PCN-flows. PCN-flows into that aggregate and raises a
                   management alarm.

1.4. Organization of This timer
                    expires when it value Document

   This document is equal to T-fail organized as follows. Section 2 gives an overview of
   RSVP extensions and operations. The elements of the used procedures
   are specified in Section 3. Section 4 describes the protocol
   elements. The security considerations are given in section 5 and is
                    reset when a report, i.e., RSVP aggregated RESV
                    message, is received for a RSVP generic aggregated
                    reservation (which is matched to one
                    ingress-egress-aggregate). the
   IANA considerations are provided in Section 6.

2.  Overview of RSVP extensions and Operations

2.1 Overview of RSVP Aggregation Procedures in PCN domains

   The PCN-boundary-nodes, see Figure 1, can support RSVP SESSIONS for
   generic aggregated reservations {RFC4860], [RFC4860], which are depending on
   ingress-egress-aggregates. In particular, one RSVP generic aggregated
   reservation matches to only one ingress-egress-aggregate.
   However, one ingress-egress-aggregate matches to either
   one or to more than one RSVP generic aggregated reservations.
   In addition, in to comply with this document specification it is considered that
   the PCN-boundary nodes are able to distinguish by usng the addresses
   that the RSVP messages are addressed to, and process (1) RSVP
   SESSIONS for generic aggregated sessions and their messages according
   to [RFC4860], (2) e2e RSVP sessions and messages according to
   [RFC2205]. Furthermore, it is considered that by configuration the
   PCN-interior-nodes are not able to distinguish neither RSVP generic
   aggregated sessions and their associated messages [RFC4860], nor e2e
   RSVP sessions and their associated messages [RFC2205].

                    --------------------------
                   /       PCN-domain         \
      |----|      |                            |      |----|
   H--| R  |\ |-----|                       |------| /| R  |-->H
   H--|    |\\|     |   |---|     |---|     |      |//|    |-->H
      |----| \|     |   | I |     | I |     |      |/ |----|
              | Agg |======================>| Deag |
             /|     |   |   |     |   |     |      |\
   H--------//|     |   |---|     |---|     |      |\\-------->H
   H--------/ |-----|                       |------| \-------->H
                  |                            |
                   \                          /
                    --------------------------

   H       = Host requesting end-to-end RSVP reservations
   R       = RSVP router
   Agg     = Aggregator (PCN-ingress-node)
   Deag    = Deaggregator (PCN-egress-node)
   I       = Interior Router (PCN-interior-node)

   -->   = E2E RSVP reservation
   ==>   = Aggregate RSVP reservation

           Figure 1 : Aggregation of E2E Reservations
            over Generic Aggregate RSVP Reservations
               in PCN domains, based on [RFC4860]

   Moreover, each Aggregator and Deaggregator (i.e., PCN-boundary-nodes)
   MUST support policies to initiate and maintain for each pair of
   PCN-boundary-nodes of the same PCN-domain (1) one ingress-egress-
   aggregate and (2) either one or more RSVP generic aggregated
   reservations.  Note that one RSVP generic aggregated reservation
   matches to only one ingress-egress-aggregate, while one ingress-
   egress-aggregate matches to either one or to more than one RSVP
   generic aggregated reservations. This can be accomplished by using
   for the different RSVP generic aggregated reservations the same
   combinations of ingress and egress identifiers, but with a different
   PHB-ID value (see [RFC4860]). The procedures for aggregation of E2E
   reservations over generic aggregate RSVP reservations are the same as
   the procedures specified in Section 4 of [RFC4860].

   Depending on a policy the Aggregator SHOULD MUST be able to decide whether
   an e2e microflow (i.e., PCN-flow) can be mapped into (1) one RSVP
   generic aggregated reservation and (2) one ingress-egress-aggregate
   maintained by the Aggregator (i.e., PCN-ingress-node). Note that each
   RSVP generic aggregated reservation is identified by using the RSVP
   SESSION object [RFC4860]. The RSVP SESSION object for generic
   aggregate reservations is based on the RSVP SESSION object specified
   in [RFC4860] augmented with the following information:

  o) the IPv4 DestAddress, IPv6 DestAddress SHOULD MUST be set to the IPv4
       or IPv6 destination addresses, respectively, of the Deaggregator
      (PCN-egress-node)
      (PCN-egress-node), see [RFC4860]. Note that the PCN-domain is
       considered as being only one RSVP hop (for Generic aggregated
       RSVP or e2e RSVP). This means that the next RSVP hop for the
       Aggregator in the downstream direction is the Deaggregator and
       the next RSVP hop for the Deaggregator in the upstream direction
       is the Aggregator. Furthermore, it is considered that for the
       determination of the Deaggregator, the same methods can be used
       as the ones described in Section 4 of [RFC4860].

    o) PHB-ID (Per Hop Behavior Identification Code) SHOULD be set equal
       to PCN-compatible Diffserv codepoint(s).

    o) Extended vDstPort SHOULD be set to the IPv4 or IPv6 destination
       addresses, of the Aggregator (PCN-ingress-node)

2.1.1 (PCN-ingress-node), see [RFC4860].

2.2   PCN Marking and encoding and transport of pre-congestion
        information

   The method of PCN marking within the PCN domain is based on
   [RFC5670]. In addition, the method of encoding and transport of pre-
   congestion information is based [RFC6660]. The PHB-ID (Per Hop
   Behavior Identification Code) used, used SHOULD be set equal
   to PCN-compatible Diffserv codepoint(s).

2.1.2.

2.3.  Traffic Classification Within The Aggregation Region

   The PCN-traffic is marked using PCN-marking and is classified using
   The PCN-ingress marks a PCN-BA useing PCN-marking (i.e., combination
   of the DSCP and ECN fields). fields), which interior nodes use to
   classify PCN-traffic. The PCN-traffic (e.g., e2e microflows)
   belonging to an ingress-
   egress-aggregate ingress-egress-aggregate can be classified only at
   the PCN-boundary-nodes using the combination of (1) PCN-BA (i.e.,
   combination of the DSCP and ECN fields), (2) IP addresses of the
   specific pair of PCN-
   boundary-nodes PCN-boundary-nodes used by a ingress-egress-aggregate. ingress-egress-
   aggregate. The method of classification and traffic conditioning of
   PCN-traffic and non-PCN traffic and PHB configuration is described in
   [RFC6661] and [RFC6662]. Moreover, the PCN-traffic (e.g., e2e
   microflows) belonging to a RSVP generic aggregated reservation can be
   classified only at the PCN-boundary-nodes (i.e., Aggregator and
   Deaggregator) by using the RSVP SESSION object for RSVP generic
   aggregated reservations, see Section 2.1 of [RFC4860]. It is
   considered that tunnels need to be used between Aggregators and
   Deaggregators, using the same procedures as specified in Section 4 of
   [RFC4860].

2.1.3.

2.4.  Deaggregator (PCN-egress-node) Determination

   In

   To comply with this document specification it is considered that for the determination of to determine
   the Deaggregator, the same methods can be used as the ones described
   in Section 4 of [RFC4860].

2.1.4.

2.5.  Mapping E2E Reservations Onto Aggregate Reservations

   In

   To comply with this document specification it is considered that for the
   mapping of e2e reservations onto aggregate reservations, the same
   methods can be used as the ones described in Section 4 of [RFC4860],
   augmented by the following rules:

   o) PCN-ingress-node MUST use one or more policies to estimate determine
      whether an e2e RSVP reservation session associated with an e2e
      Path message that arrives at the external interface of the PCN-ingress-
      node PCN-
      ingress-node can be mapped onto an existing RSVP generic
      aggregation reservation state.

2.1.5.

2.6.  Size of Aggregate Reservations

   In

   To comply with this document specification it is considered that for the
   determination of the size of the RSVP generic aggregate reservations,
   the same methods can be used as the ones described in [RFC4860].

2.1.6. [RFC4860] and
   Section 1.4.4. of [RFC3175].

2.7.  E2E Path ADSPEC update

   In

   To comply with this document specification it is considered that for the
   update of the e2e Path ADSPEC, the same methods can be used as the
   ones described in [RFC4860].

2.1.7.

2.8.  Intra-domain Routes

   The PCN-interior-nodes are neither maintaining e2e RSVP nor RSVP
   generic aggregation states and reservations. Therefore, intra-domain
   route changes will not affect intra-domain reservations since such
   reservations are not maintained by the PCN-interior-nodes.

2.1.8.
   Furthermore, it is considered that by configuration, the PCN-
   interior-nodes are not able to distinguish neither RSVP generic
   aggregated sessions and their associated messages [RFC4860], nor e2e
   RSVP sessions and their associated messages [RFC2205].

2.9.  Inter-domain Routes

   In this document it is considered that

   The PCN-charter scope precludes inter-domain considerations. However,
   for the solving inter-domain routes changes associated with the issues
   caused by operation
   of the inter-domain route changes, RSVP messages, the same methods can SHOULD be used as the ones
   described in [RFC4860].

2.1.9. [RFC4860] and in Section 1.4.7 of
   [RFC3175].

2.10.  Reservations for Multicast Sessions

   PCN does not consider reservations for multicast sessions.

2.1.10.

2.11.  Multi-level Aggregation

   PCN does not consider multi-level aggregations within the PCN domain.

2.1.11.
   Therefore, the PCN-interior-nodes are not supporting multi-level
   aggregation procedures. However, the Aggregator and Deaggregator
   SHOULD support the multi-level aggregation procedures specified in
   [RFC4860] and in Section 1.4.9 of [RFC3175].

2.12.  Reliability Issues

   In

   To comply with this document specification it is considered that for solving
   possible reliability issues, the same methods can be used as the ones
   described in Section 4 of [RFC4860].

2.1.12.

2.13.  Message Integrity and Node Authentication

   In

   To comply with this document specification it is considered that for message
   integrity and node authentication, the same methods can be used as
   the ones described in Section 4 of [RFC4860] and [RFC5559].

3. Elements of Procedure

   This section describes the procedures used to implement the
   aggregated RSVP procedure over PCN. It is considered that the
   procedures for aggregation of e2e reservations over generic aggregate
   RSVP reservations are the same as the procedures specified in Section
   4 of [RFC4860].

3.1.  Receipt of E2E Path Message By PCN-ingress-node (aggregating
      router)

   When the e2e RSVP message arrives at the exterior interface of the
   Aggregator, i.e., PCN-ingress-node, then standard RSVP generic
   aggregation [RFC4860] procedures are used, augmented with the
   following rules:

     o) The e2e RSVP reservation session associated with an e2e Path
        message that arrives at the external interface of the PCN-
        ingress-node is mapped/matched onto an existing RSVP generic
        aggregation reservation state.

     o) If the timer t-recvFail expires for a given PCN-egress-node, the
        Decision Point (i.e., PCN-ingress-node) SHOULD NOT
        allow the e2e microflow (i.e., PCN-flow) to be admitted to that
        RSVP generic aggregated reservation (which is matched to one
        ingress-egress-aggregate). The admission or rejection procedure
        of a PCN-flow into the PCN-domain is defined in detail in:
        [RFC6661] and [RFC6662].
        If the Aggregator is not able to admit the e2e microflow it
        SHOULD then generate an e2e PathErr message using standard e2e
        RSVP procedures [RFC4495]. This e2e PathErr message is sent to
        the originating sender of the e2e Path message. A new error code
        "PCN-domain rejects e2e reservation" MUST be augmented to the
        RSVP error codes to inform the sender that a PCN domains rejects interface of the e2e PCN-
        ingress-node is mapped/matched onto an existing RSVP generic
        aggregation reservation request. state.

     o) If the timer t-recvFail does NOT expire for a given PCN-egress-
        node, then:

         o) If (1) the PCN-admission state for the ingress-egress-
            aggregate associated with the received e2e Path and (2) the
            state for the selected RSVP generic aggregated reservation,
            see [RFC4860], are "admit", the Decision Point (i.e., PCN-
            ingress-node) SHOULD allow the new flow to be admitted to
            that RSVP generic aggregated reservation. reservation, see [RFC6661] and
            [RFC6662]. The e2e Path message is then forwarded towards
            destination.

         o) If for the same ingress-egress-aggregated ingress-egress-aggregate and the same RSVP
            generic aggregated reservation then (1) the PCN-admission-
            state and/or (2) the state for the RSVP generic aggregated
            reservation are/is "block", the flow SHOULD NOT be
            admitted by the Aggregator and an e2e PathErr message SHOULD
            be generated, using standard e2e RSVP procedures
            [RFC4495]. This e2e PathErr message is sent to the
            originating sender of the e2e Path message, using standard
            e2e RSVP procedures [RFC2205], [RFC4495]. A new error code
            "PCN-domain rejects e2e reservation" MUST be augmented to
            the RSVP error codes to inform the sender that a PCN domains
            rejects the e2e reservation request.

    o) If the timer t-recvFail expires for a given PCN-egress-node, the
        Decision Point (i.e., PCN-ingress-node) SHOULD NOT
        allow the e2e microflow (i.e., PCN-flow) to be admitted to that
        RSVP generic aggregated reservation (which is matched to one
        ingress-egress-aggregate), see [RFC6661], [RFC6662]. The
        admission or rejection procedure of a PCN-flow into the PCN-
        domain is defined in detail in: [RFC6661] and [RFC6662].
        If the Aggregator is not able to admit the e2e microflow it
        SHOULD then generate an e2e PathErr message using standard e2e
        RSVP procedures [RFC4495]. This e2e PathErr message is sent to
        the originating sender of the e2e Path message. The e2e RSVP
        error code "01: Admission Control failure" and the "Sub-code =
        2: Requested bandwidth unavailable " specified in Appendix B of
        [RFC2205] SHOULD be used for this purpose.

   The way of how the PCN-admission-state is maintained is specified in
   [RFC6661] and [RFC6662]. The way of how the RSVP generic aggregated
   reservation state is maintained is specified in [RFC4860].

3.2.  Handling Of E2E Path Message By Interior Routers

   The e2e Path messages traverse zero or more PCN-interior-nodes.

   The PCN-interior-nodes receive the e2e Path message on an interior
   interface and forward it on another interior interface. The It is
   considered that by configuration the PCN-interior-nodes are not able
   to distinguish neither e2e RSVP sessions and their associated
   messages [RFC2205]. Therefore, the e2e Path messages are simply
   forwarded as normal IP datagrams.

3.3.  Receipt of E2E Path Message By PCN-egress-node (deaggregating
      router)

   When receiving the e2e Path message the PCN-egress-node
   (Deaggregator) performs main regular [RFC4860] procedures, augmented
   with the following rules, see also [draft-lefaucheur-rsvp-ecn-01]:

     o) The PCN-egress-node MUST NOT perform the RSVP-TTL vs IP TTL-
         check and MUST NOT update the ADspec Break bit. This is because
         the whole PCN-domain is effectively handled by e2e RSVP as a
         virtual link on which integrated service is indeed supported
         (and admission control performed) so that the Break bit MUST
         NOT be set.

    The PCN-egress-nodes forwards the e2e Path message towards the
    receiver.

3.4.  Initiation of new Aggregate Path Message By PCN-ingress-node
      (Aggregating Router)

   In

   To comply with this document specification it is considered that for the
   initiation of the new RSVP aggregated Path message by the PCN-ingress-node PCN-
   ingress-node (Aggregator), the same methods can be used as the ones
   described in [RFC4860].

3.5.  Handling Of new Aggregate Path Message By Interior Routers

   The Aggregate Path messages traverse zero or more PCN-interior-nodes.
   The PCN-interior-nodes receive the e2e Path message on an interior
   interface and forward it on another interior interface. The
   It is considered that by configuration, the PCN-interior-nodes are
   not able to distinguish neither RSVP generic aggregated sessions and
   their associated messages [RFC4860]. Therefore, the Aggregated Path
   messages are simply forwarded as normal IP datagrams.

3.6.  Handling of E2E Resv Message by Deaggregating Router

   When the e2e Resv message arrives at the exterior interface of the
   Deaggregator, i.e., PCN-egress-node, then standard RSVP
   aggregation [RFC4860] procedures are used.

3.7.  Handling Of E2E Resv Message By Interior Routers

   The e2e Resv messages traverse zero or more PCN-interior-nodes. The
   PCN-interior-nodes receive the e2e Resv message on an interior
   interface and forward it on another interior interface. The It is
   considered that by configuration the PCN-interior-nodes are not able
   to distinguish neither e2e RSVP sessions and their associated
   messages [RFC2205]. Therefore, the e2e Resv messages are simply
   forwarded as normal IP datagrams.

3.8.  Initiation of New Aggregate Resv Message By Deaggregating Router

   In

   To comply with this document specification it is considered that for the
   initiation of the new RSVP aggregated Resv message by the PCN-ingress-node PCN-
   ingress-node (Aggregator), the same methods can be used as the ones
   described in Section 4 of [RFC4860] augmented with the following
   rules:

     o) At the end of each t-meas measurement interval, or less
        frequently if "optional report suppression" is activated, see
        [RFC6661], and [RFC6662], the PCN-egress-node MUST include the
        new PCN object that will be sent to the associated Decision
        Point (i.e., PCN-ingress-node). The PCN object is specified in
        this document and is used for the report of PCN-egress-node reports the
        data measured by
        the PCN-egress-node, it measures for a particular ingress-egress-aggregate,
        see ingress-egress-aggregate in a
        PCN object, as specified in Section 4 of this document (see
        [RFC6661], and [RFC6662]. [RFC6662]). The address of the PCN-ingress-
        node
        node, i.e., Aggregator, is the one specified in the same
        ingress-egress-aggregate. It is considered that the ingress-
        egress-aggregate state stores both IP addresses of the PCN-
        ingress-node, i.e., Aggregator, and of the IP-egress-node, i.e.,
        Deaggregator.

3.9.  Handling of Aggregate Resv Message by Interior Routers

   The Aggregated Resv messages traverse zero or more PCN-interior-
   nodes. The PCN-interior-nodes receive the Aggregated Resv message on
   an interior interface and forward it on another interior interface.
   The
   It is considered that by configuration, the PCN-interior-nodes are
   not able to distinguish neither RSVP generic aggregated sessions and
   their associated messages [RFC4860]. Therefore, the Aggregated Resv
   messages are simply forwarded as normal IP datagrams.

3.10.  Handling of E2E Resv Message by Aggregating Router

   When the e2e Resv message arrives at the interior interface of the
   Aggregating router, i.e., PCN-ingress-node, then standard RSVP
   aggregation [RFC4860] procedures are used.

3.11.  Handling of Aggregated Resv Message by Aggregating Router

   When the Aggregated Resv message arrives at the interior interface of
   the Aggregating router, i.e., PCN-ingress-node, then standard RSVP
   aggregation [RFC4860] procedures are used, augmented with the
   following rules:

    o)  If the Decision Point (i.e., is not collocated with the PCN-ingress-node) PCN-ingress-
        node, then other procedures need to be specified of handling the
        Aggregated Resv Message by the Aggregating router, i.e., PCN-
        ingress-node. These procedures are out of the scope of this
        document.

    o)  If the Decision point is collocated with the PCN-ingress-node,
        then the PCN-ingress-node (i.e. Aggregator) SHOULD use the
        information carried by the PCN objects as specified in
        [RFC6661], [RFC6662]. When the Aggregator (i.e.,
        PCN-ingress-node) PCN-ingress-
        node) needs to terminate an amount of traffic associated to with
        one ingress-egress-aggregate (see bullet 2 in Section 3.3.2 of
        [RFC6661] and [RFC6662]), then several procedures of terminating
        e2e microflows can be deployed. The default procedure of
        terminating e2e microflows (i.e., PCN-flows) is as follows, see
        e.g., [RFC6661].

        For the same ingress-egress-aggregate, select a number of e2e
        microflows to be terminated in order to decrease the total
        incoming amount of bandwidth associated with one ingress-egress-aggregate ingress-egress-
        aggregate by the amount of traffic to be terminated, see above.
        In this situation the same mechanisms for terminating an e2e
        microflow can be followed as specified in [RFC2205]. However,
        based on a local policy, the Aggregator could use other procedures ways of terminating microflows.
        selecting which microflows should be terminated.
        For example, for the same ingress-egress-aggregate, select a
        number of e2e microflows to be terminated or to reduce their
        reserved bandwidth in order to decrease the total incoming
        amount of bandwidth associated with one ingress-egress-aggregate
        by the amount of traffic to be terminated. In this situation the
        same mechanisms for terminating an e2e microflow or reducing
        bandwidth associated with an e2e microflow can be followed as
        specified in [RFC4495].

3.12.  Removal of E2E Reservation

   In

   To comply with this document specification it is considered that for the
   removal of e2e reservations, the same methods can be used as the ones
   described in Section 4 of [RFC4860] and [RFC4495]. [RFC4495], augmented by the
   methods described in Section 3.11.

3.13.  Removal of Aggregate Reservation

   In

   To comply with this document specification it is considered that for the
   removal of RSVP generic aggregated reservations, the same methods can
   be used as the ones described in [RFC4860]. Section 4 of [RFC4860] and Section
   2.10 of [RFC3175]. In particular, should an aggregate reservation go
   away (presumably due to a configuration change, route change, or
   policy event), the e2e reservations it supports are no longer active.
   They must be treated accordingly.

3.14.  Handling of Data On Reserved E2E Flow by Aggregating Router

   The handling of data on the reserved e2e Flow by Aggregating Router
   is using the procedures described in [RFC4860] augmented with:

   o)  Regarding, PCN marking and traffic classification the procedures
       defined in Section 2.1.1 2.2 and 2.1.3 2.4 of this document are used.

3.15.  Procedures for Multicast Sessions

   In this document no multicast sessions are considered.

4.  Protocol Elements

   The protocol elements in this document are using the protocol
   Elements
   elements defined in [RFC4860], Section 4 [RFC4860] and Section 3 of [RFC3175]
   augmented with the following rules:

  o) A PCN-egress-node (i.e., Deaggregator) SHOULD send periodically
      and at the end of each t-meas measurement interval, or less
      frequently if "optional report suppression" is activated, an
      (refresh) aggregated RSVP message to the PCN-ingress-node (i.e.
      aggregator).
      aggregator), see [RFC6661] and [RFC6662].

   o) the DSCP value included in the SESSION object, SHOULD be set equal
      to a PCN-compatible Diffserv codepoint.

   o) An aggregated Resv message MUST carry one or more C-type PCN
      objects, see Section 4.1, to report the data measured by an
      PCN-egress-node (i.e., Deaggregator).

   o) As described in [RFC6661], [RFC6663], PCN reports
      from the PCN-egress-node (Deaggregator) to the decision point may
      contain flow identifiers for individual flows within an
      ingress-egress-aggregate that have recently experienced
      excess-marking. Hence, the PCN report messages used by the PCN CL
      edge behavior MUST be capable of carrying sequences of octet
      strings constituting such identifiers. When the PCN CL edge
      behavior is used, the individual flow identifiers need to be
      included in specific PCN objects, see Section 4.1
      (C-Type = RSVP-AGGREGATE-IPv4-PCN-CL-FLIDs,
              = RSVP-AGGREGATE-IPv6-PCN-CL-FLIDs)

4.1 PCN object

   The PCN object reports data measured by an PCN-egress-node. a PCN-egress-node and
   carried by the generic aggregated RESV messages specified in
   [RFC4860]. PCN objects are defined for different PCN edge behavior
   drafts. This document defines several six types of PCN objects. objects:

   o) Single Marking (SM) PCN object, when IPv4 addresses are used:
      Class = PCN
      C-Type = RSVP-AGGREGATE-IPv4-PCN-SM

        +-------------+-------------+-------------+-------------+
        |     IPv4 PCN-ingress-node Address (4 bytes)           |
        +-------------+-------------+-------------+-------------+
        |     IPv4 PCN-egress-node Address (4 bytes)            |
        +-------------+-------------+-------------+-------------+
        |       rate of not marked PCN-traffic (NM-rate)        |
        +-------------+-------------+-------------+-------------+
        |       rate of PCN-marked PCN-traffic (PM-rate)        |
        +-------------+-------------+-------------+-------------+

   o) Single Marking (SM) PCN object, when IPv6 addresses are used:
      Class = PCN
      C-Type = RSVP-AGGREGATE-IPv6-PCN-SM

        +-------------+-------------+-------------+-------------+
        |                                                       |
        +                                                       +
        |                                                       |
        +     IPv6 PCN-ingress-node Address (16 bytes)          +
        |                                                       |
        +                                                       +
        |                                                       |
        +-------------+-------------+-------------+-------------+
        |                                                       |
        +                                                       +
        |                                                       |
        +     IPv6 PCN-egress-node Address (16 bytes)           +
        |                                                       |
        +                                                       +
        |                                                       |
        +-------------+-------------+-------------+-------------+
        |       rate of not marked PCN-traffic (NM-rate)        |
        +-------------+-------------+-------------+-------------+
        |       rate of PCN-marked PCN-traffic (PM-rate)        |
        +-------------+-------------+-------------+-------------+

   o) Controlled (CL) PCN object, IPv4 addresses are used:
      Class = PCN
      C-Type = RSVP-AGGREGATE-IPv4-PCN-CL

        +-------------+-------------+-------------+-------------+
        |     IPv4 PCN-ingress-node Address (4 bytes)           |
        +-------------+-------------+-------------+-------------+
        |     IPv4 PCN-egress-node Address (4 bytes)            |
        +-------------+-------------+-------------+-------------+
        |       rate of not marked PCN-traffic (NM-rate)        |
        +-------------+-------------+-------------+-------------+
        |  rate of threshold-marked PCN-traffic (ThM-rate)      |
        +-------------+-------------+-------------+-------------+
        |  rate of excess-traffic-marked PCN-traffic (ETM-rate) |
        +-------------+-------------+-------------+-------------+

   o) Controlled (CL) PCN object, IPv6 addresses are used:
      Class = PCN
      C-Type = RSVP-AGGREGATE-IPv6-PCN-CL

        +-------------+-------------+-------------+-------------+
        |                                                       |
        +                                                       +
        |                                                       |
        +     IPv6 PCN-ingress-node Address (16 bytes)          +
        |                                                       |
        +                                                       +
        |                                                       |
        +-------------+-------------+-------------+-------------+
        |                                                       |
        +                                                       +
        |                                                       |
        +     IPv6 PCN-egress-node Address (16 bytes)           +
        |                                                       |
        +                                                       +
        |                                                       |
        +-------------+-------------+-------------+-------------+
        |       rate of not marked PCN-traffic (NM-rate)        |
        +-------------+-------------+-------------+-------------+
        |  rate of threshold-marked PCN-traffic (ThM-rate)      |
        +-------------+-------------+-------------+-------------+
        |  rate of excess-traffic-marked PCN-traffic (ETM-rate) |
        +-------------+-------------+-------------+-------------+

   The fields carried by the PCN object are specified in
   [RFC6663], [RFC6661] and [RFC6662]:

     o the IPv4 or IPv6 address of the PCN-ingress-node and the IPv4
       or IPv6 address of the PCN-egress-node; together they specify the
       ingress-egress-aggregate to which the report refers; refers. According to
       [RFC6663] the report should carry the identifier of the PCN-
       ingress-node and the identifier of the PCN-egress-node (typically
       their IP addresses);

     o rate of not-marked PCN-traffic (NM-rate) in octets/second; its
       format is a 32-bit IEEE floating point number;

     o rate of PCN-marked traffic (PM-rate) in octets/second; its format
       is a 32-bit IEEE floating point number;

     o rate of threshold-marked PCN traffic (ThM-rate) in
       octets/second; its format is a 32-bit IEEE floating point number;

     o rate of excess-traffic-marked traffic (ETM-rate) in
       octets/second; its format is a 32-bit IEEE floating point number;

   o) Controlled (CL) PCN CL Flow IDs object, IPv4 addresses are used:
      Class = PCN
      C-Type = RSVP-AGGREGATE-IPv4-PCN-CL-FLIDs

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
                                                   +-+-+-+-+-+-+-+-+
                                                   | Length        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Source Address                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Destination Address                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Source Port          |       Destination Port        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Protocol    |      Reserved                                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                                                             //
   +                                                               +
   |                       Source Address                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Destination Address                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Source Port          |       Destination Port        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Protocol    |      Reserved                                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      o)  Length (1 byte): the length of the
          RSVP-AGGREGATE-IPv4-PCN-CL-FLIDs object in units of 16 bytes.
          This field is used to specify the number of IPv4 flow IDs
          carried by this object. Each flow ID is represented by the
          combination of each subsequent 5 tuple:
          Source address, Destination address, Source Port,
          Destination Port and Protocol number.
          If Length is 0 then the RSVP-AGGREGATE-IPv4-PCN-CL-FLIDs is
          empty.

      o) Source address (4 bytes):  The IPv4 source address.

      o) Destination address (4 bytes): The IPv4 destination address.

      o) Protocol (1 byte):  The IP protocol number. It refers to the
         true upper layer protocol carried by the packets.

      o) Source Port (2 bytes): contains the source port number.

      o) Destination Port (2 bytes): contains the destination port
         number.

   o) Controlled (CL) PCN CL Flow IDs object, IPv6 addresses are used:
      Class = PCN
      C-Type = RSVP-AGGREGATE-IPv6-PCN-CL-FLIDs

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
                                                   +-+-+-+-+-+-+-+-+
                                                   | Length        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                       Source Address                          |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                      Destination Address                      |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Source Port          |       Destination Port        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Protocol    |      Reserved                                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                                                             //
   +                                                               +
   |                                                               |
   |                       Source Address                          |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                       Destination Address                     |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Source Port          |       Destination Port        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Protocol    |      Reserved                                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      o) Length (1 byte): the length of the
         RSVP-AGGREGATE-IPv6-PCN-CL-FLIDs object in units of 40 bytes.
         This field is used to specify the number of flow IDs carried by
         this object. Each flow ID is represented by the combination of
         each subsequent 5 tuple fields:
         Source address, Destination address, Source Port,
         Destination Port and Protocol number.
         If Length is 0 then the RSVP-AGGREGATE-IPv6-PCN-CL-FLIDs object
         is empty.

      o) Source address (16 bytes):  The IPv6 source address.

      o) Destination address (16 bytes): The IPv6 destination address.

      o) Protocol (1 byte):  The IP protocol number. It refers to the
          true upper layer protocol carried by the packets.

      o) Source Port (2 bytes): contains the source port number.

      o) Destination Port (2 bytes): contains the destination port
         number.

5.  Security Considerations

   The same security considerations specified in [RFC4860] and [RFC2205], [RFC4230],
   [RFC4860], [RFC5559]
   apply also to this document. and [RFC6411].

6.  IANA Considerations

   This document makes the following requests to the IANA:
      o allocate a new Object Class (PCN Object), see Section 4.1.

      o allocate a "PCN-domain rejects e2e reservation" Error Code that
        may appear only in e2e PathErr messages, see Section 3.1.

7.  Acknowledgments

   We would like to thank the authors of [draft-lefaucheur-rsvp-ecn-
   01.txt], since some ideas used in this document are based on the work
   initiated in [draft-lefaucheur-rsvp-ecn-01.txt]. Moreover, we would
   like to thank Tom Taylor, Philip Eardley, Michael Menth,
   Toby Moncaster, Francois Le Faucheur and James Polk for the provided
   comments.

8.  Normative References

   [RFC6661] T. Taylor, A, Charny, F. Huang,
   G. Karagiannis, M. Menth, "PCN Boundary Node Behaviour for the
   Controlled Load (CL) Mode of Operation", July
   2012.

   [RFC6662] A. Charny, J. Zhang,
   G.  Karagiannis, M. Menth, T. Taylor, "PCN Boundary Node Behaviour
   for the Single Marking (SM) Mode of Operation",
   July 2012.

   [RFC6663] G. Karagiannis, T. Taylor,
   K. Chan, M. Menth, P. Eardley, " Requirements for Signaling of (Pre-)
   Congestion Information in a DiffServ Domain",
   July 2012.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
    Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2205] Braden, R., ed., et al., "Resource ReSerVation Protocol
   (RSVP)- Functional Specification", RFC 2205, September 1997.

   [RFC3140] Black, D., Brim, S., Carpenter, B., and F. Le
   Faucheur, "Per Hop Behavior Identification Codes",
   RFC 3140, June 2001.

   [RFC3175] Baker, F., Iturralde, C., Le Faucheur, F., and B. Davie,
   "Aggregation of RSVP for IPv4 and IPv6 Reservations", RFC 3175,
   September 2001.

   [RFC4495] Polk, J. and S. Dhesikan, "A Resource Reservation
   Protocol (RSVP) Extension for the Reduction of
   Bandwidth of a Reservation Flow", RFC 4495, May 2006.

   [RFC4860] F. Le Faucheur, B. Davie, P. Bose, C. Christou, M.
   Davenport, "Generic Aggregate Resource ReSerVation Protocol (RSVP)
   Reservations", RFC4860, May 2007.

   [RFC5670] Eardley, P., "Metering and Marking Behaviour of PCN-Nodes",
    RFC 5670, November 2009.

   [RFC6660]  Moncaster, T., Briscoe, B., and M. Menth, "Baseline
    Encoding and Transport of Pre-Congestion Information", RFC 6660,
    July 2012.

9.  Informative References

   [draft-lefaucheur-rsvp-ecn-01.txt] Le Faucheur, F., Charny, A.,
   Briscoe, B., Eardley, P., Chan, K., and J. Babiarz, "RSVP Extensions
   for Admission Control over Diffserv using Pre-congestion
   Notification (PCN) (Work in progress)", June 2006.

   [RFC1633]  Braden, R., Clark, D., and S. Shenker, "Integrated
   Services in the Internet Architecture: an Overview", RFC 1633, June
   1994.

   [RFC2211] J. Wroclawski, Specification of the Controlled-Load Network
   Element Service, September 1997

   [RFC2212] S. Shenker et al., Specification of Guaranteed Quality of
   Service, September 1997

   [RFC2474]  Nichols, K., Blake, S., Baker, F., and D. Black,
   "Definition of the Differentiated Services Field (DS Field) in the
   IPv4 and IPv6 Headers", RFC 2474, December 1998.

   [RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z. and
   W. Weiss, "A framework for Differentiated Services", RFC 2475,
   December 1998.

   [RFC2998] Bernet, Y., Yavatkar, R., Ford, P., Baker, F., Zhang, L.,
   Speer, M., Braden, R., Davie, B., Wroclawski, J. and E. Felstaine, "A
   Framework for Integrated Services Operation Over DiffServ Networks",
   RFC 2998, November 2000.

   [RFC4230] H. Tschofenig, R. Graveman, "RSVP Security Properties",
   RFC 4230, December 2005.

   [RFC5559]  Eardley, P., "Pre-Congestion Notification (PCN)
   Architecture", RFC 5559, June 2009.

   [RFC6411] M. Behringer, F. Le Faucheur, B. Weis, "Applicability of
   Keying Methods for RSVP Security", RFC 6411, October 2011.

   [SIG-NESTED] Baker, F. and P. Bose, "QoS Signaling in a Nested
   Virtual Private Network", Work in Progress, February 2007.

10.  Authors' Address

   Georgios Karagiannis
   University of Twente
   P.O. Box 217
   7500 AE Enschede,
   The Netherlands
   EMail: g.karagiannis@utwente.nl

   Anurag Bhargava
   Cisco Systems, Inc.
   7100-9 Kit Creek Road
   PO Box 14987
   RESEARCH TRIANGLE PARK, NORTH CAROLINA 27709-4987
   USA
   Email: anuragb@cisco.com