Network Working Group                                       M. Behringer
Internet-Draft                                            F. Le Faucheur
Intended status: Informational                         Cisco Systems Inc
Expires: August 21, 2008                               February 18, 2008

           Applicability of Keying Methods for RSVP Security

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at

   The list of Internet-Draft Shadow Directories can be accessed at

   This Internet-Draft will expire on August 21, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2008).


   The Resource reSerVation Protocol (RSVP) allows hop-by-hop
   authentication of RSVP neighbors.  This requires messages to be
   cryptographically signed using a shared secret between participating
   nodes.  This document compares group keying for RSVP with per
   neighbor or per interface keying, and discusses the associated key
   provisioning methods as well as applicability and limitations of
   these approaches.  Draft-weis-gdoi-for-rsvp provides an example of
   how the Group Domain of Interpretation (GDOI) could be used to

Behringer & Le Faucheur  Expires August 21, 2008                [Page 1]

Internet-Draft          RSVP Keying Applicability          February 2008

   distribute group keys to RSVP nodes.  The present document also
   discusses applicability of group keying to RSVP encryption.

Table of Contents

   1.  Introduction and Problem Statement . . . . . . . . . . . . . .  3
   2.  The RSVP Trust Model . . . . . . . . . . . . . . . . . . . . .  3
   3.  Key types for RSVP . . . . . . . . . . . . . . . . . . . . . .  4
     3.1.  Interface based keys . . . . . . . . . . . . . . . . . . .  4
     3.2.  Neighbor based keys  . . . . . . . . . . . . . . . . . . .  5
     3.3.  Group keys . . . . . . . . . . . . . . . . . . . . . . . .  5
   4.  Key Provisioning Methods for RSVP  . . . . . . . . . . . . . .  5
     4.1.  Static Key Provisioning  . . . . . . . . . . . . . . . . .  5
     4.2.  Per Neighbor Key Negotiation . . . . . . . . . . . . . . .  6
     4.3.  Dynamic Group Key Distribution . . . . . . . . . . . . . .  6
   5.  Applicability of Various Keying Methods for RSVP . . . . . . .  6
     5.1.  Per Neighbor or Per Interface Keys for Authentication  . .  6
     5.2.  Group Keys for Authentication  . . . . . . . . . . . . . .  6
     5.3.  Non-RSVP Hops  . . . . . . . . . . . . . . . . . . . . . .  7
     5.4.  Subverted RSVP Nodes . . . . . . . . . . . . . . . . . . .  8
     5.5.  RSVP Encryption  . . . . . . . . . . . . . . . . . . . . .  9
     5.6.  RSVP Notify Messages . . . . . . . . . . . . . . . . . . .  9
   6.  End Host Considerations  . . . . . . . . . . . . . . . . . . . 10
   7.  Applicability to Other Architectures and Protocols . . . . . . 10
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11
   9.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 11
   10. Changes to Previous Version  . . . . . . . . . . . . . . . . . 11
     10.1. changes from behringer-00 to behringer-01  . . . . . . . . 11
     10.2. changes from behringer-01 to ietf-00 . . . . . . . . . . . 12
   11. Informative References . . . . . . . . . . . . . . . . . . . . 12
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13
   Intellectual Property and Copyright Statements . . . . . . . . . . 14

Behringer & Le Faucheur  Expires August 21, 2008                [Page 2]

Internet-Draft          RSVP Keying Applicability          February 2008

1.  Introduction and Problem Statement

   The Resource reSerVation Protocol [RFC2205] allows hop-by-hop
   authentication of RSVP neighbors, as specified in [RFC2747].  In this
   mode, an integrity object is attached to each RSVP message to
   transmit a keyed message digest.  This message digest allows the
   recipient to verify the authenticity of the RSVP node that sent the
   message, and to validate the integrity of the message.  Through the
   inclusion of a sequence number in the scope of the digest, the digest
   also offers replay protection.

   [RFC2747] does not dictate how the key for the integrity operation is
   derived.  Currently, most implementations of RSVP use a statically
   configured key, per interface or per neighbor.  However, to manually
   configure key per router pair across an entire network is
   operationally hard, especially for key changes.  Effectively, many
   users of RSVP therefore resort to the same key throughout their
   network, and change it rarely if ever, because of the operational
   burden.  [RFC3562] however recommends regular key changes, at least
   every 90 days.

   [I-D.weis-gdoi-for-rsvp] provides an example of how group keys could
   be dynamically distributed to a set of RSVP routers and updated,
   using GDOI ([RFC3547]) for the actual key distribution.

   The present document discusses the various keying methods and their
   applicability to different RSVP deployment environments, for both
   message integrity and encryption.  It does not mandate any particular
   method, but is meant as a comparative guideline to understand where
   each RSVP keying method is best deployed, and its limitations.
   Furthermore, it discusses how RSVP hop by hop authentication is
   impacted in the presence of non-RSVP nodes, or subverted nodes, in
   the reservation path.

   The document "RSVP Security Properties" ([RFC4230]) provides an
   overview of RSVP security, including RSVP Cryptographic
   Authentication [RFC2747], but does not discuss key management.  It
   states that "RFC 2205 assumes that security associations are already
   available".  The present document focuses specifically on key
   management with different key types, including group keys.  Therefore
   this document complements [RFC4230].

2.  The RSVP Trust Model

   Many protocol security mechanisms used in networks require and use
   per peer authentication.  Each hop authenticates its neighbor with a
   shared key or certificate.  This is also the model used for RSVP.

Behringer & Le Faucheur  Expires August 21, 2008                [Page 3]

Internet-Draft          RSVP Keying Applicability          February 2008

   Trust in this model is transitive.  Each RSVP node trusts explicitely
   only its RSVP next hop peers, through the message digest contained in
   the INTEGRITY object.  The next hop RSVP speaker in turn trusts its
   own peers and so on.  See also the document ""RSVP security
   properties" [RFC4230] for more background.

   The keys used for generating the RSVP messages can, in particular, be
   group keys (for example distributed via GDOI [RFC3547], as discussed
   in [I-D.weis-gdoi-for-rsvp]).  The trust model is the same as for
   RSVP authentication.  This is described in more detail in the section
   "Using GDOI For RSVP Encryption" in section 5.5.

   The trust an RSVP node has to another RSVP node has an explicit and
   an implicit component.  Explicitely the node trusts the other node to
   maintain the RSVP messages intact or confidential, depending on
   whether authentication or encryption (or both) is used.  This means
   only that the message has not been altered or seen by another, non-
   trusted node.  Implicitely each node trusts each other node with
   which it has a trust relationship established via the mechanisms here
   to adhere to the protocol specifications laid out by the various
   standards.  Note that in any group keying scheme like GDOI a node
   trusts explicitely as well as implicitely all the other members of
   the group.

   The RSVP protocol can operate in the presence of a non-RSVP router in
   the path from the sender to the receiver.  The non-RSVP hop will
   ignore the RSVP message and just pass it along.  The next RSVP node
   can then process the RSVP message.  For RSVP authentication to work
   in this case, the key used for computing the RSVP message digest
   needs to be shared by the two RSVP neighbors, even if they are not IP
   neighbors.  However, in the presence of non-RSVP hops, while an RSVP
   node always know the next IP hop before forwarding an RSVP Message,
   it does not always know the RSVP next hop.  Thus, the presence of
   non-RSVP hops impacts operation of RSVP authentication and may
   influence the keying approaches.  This is further discussed in
   Section 5.3.

3.  Key types for RSVP

3.1.  Interface based keys

   Most current RSVP authentication implementations support interface
   based RSVP keys.  When the interface is point-to-point (and therefore
   an RSVP router only has a single RSVP neighbor on each interface),
   this is similar to neighbor based keys in the sense that a different
   key is used for each neighbor.  However, when the interface is
   multipoint, all RSVP speakers on a given subnet have to share the

Behringer & Le Faucheur  Expires August 21, 2008                [Page 4]

Internet-Draft          RSVP Keying Applicability          February 2008

   same key in this model, which makes it unsuitable for deployment
   scenarios where different trust groups share a subnet, for example
   Internet exchange points.  In such a case, neighbor based keys are

3.2.  Neighbor based keys

   In this model, an RSVP key is bound to an interface plus a neighbor
   on that interface.  It allows the distinction of different trust
   groups on a single subnet.  (Assuming that layer-2 security is
   correctly implemented to prevent layer-2 attacks.)

3.3.  Group keys

   Here, all members of a group of RSVP nodes share the same key.  This
   implies that a node uses the same key regardless of the next RSVP hop
   that will process the message (within the group of nodes sharing the
   particular key).  It also implies that a node will use the same key
   on the receiving as on the sending side (when exchanging RSVP
   messages withn the group).

4.  Key Provisioning Methods for RSVP

4.1.  Static Key Provisioning

   The simplest way to implement RSVP authentication is to use static,
   preconfigured keys.  Static keying can be used with interface based
   keys, neighbor based keys or group keys.

   However, such static key provisioning is expensive on the operational
   side, since no secure automated mechanism can be used, and initial
   provisioning as well as key updates require configuration.  This
   method is therefore mostly useful for small deployments, where key
   changes can be carried out manually, or for deployments with
   automated configuration tools which support key changes.

   Static key provisioning is therefore not an ideal model in a large

   Often, the number of interconnection points across two domains where
   RSVP is allowed to transit is relatively small and well controlled.
   Also, the different domains may not be in a position to use an
   infrastructure trusted by both domains to update keys on both sides.
   Thus, manually configured keys may be applicable to inter-domain RSVP

   Since it is not practical to carry out the key change at the exact

Behringer & Le Faucheur  Expires August 21, 2008                [Page 5]

Internet-Draft          RSVP Keying Applicability          February 2008

   same time on both sides, some grace period needs to be implemented
   during which an RSVP node will accept both the old and the new key.
   Otherwise, RSVP operation would suffer interruptions.

4.2.  Per Neighbor Key Negotiation

   To avoid the problem of manual key provisioning and updates in static
   key deployments, key negotiation between RSVP neighbors could be
   used.  Key negotiation could be used to derive either interface or
   neighbor based keys.  However, existing key negotiation protocols
   such as IKEv1[RFC2409] or IKEv2 [RFC4306] may not be appropriate in
   all environments because of the relative complexity of the protocols
   and related operations.

4.3.  Dynamic Group Key Distribution

   With this approach, group keys are dyanmically distributed among a
   set of RSVP routers.  For example, [I-D.weis-gdoi-for-rsvp] describes
   a mechanism to distribute group keys to a group of RSVP speakers,
   using GDOI [RFC3547].  In this solution, a key server authenticates
   each of the RSVP nodes independently, and then distributes a group
   key to the entire group.

5.  Applicability of Various Keying Methods for RSVP

5.1.  Per Neighbor or Per Interface Keys for Authentication

   Per interface and per neighbor keys can be used within a single
   security domain.  As mentioned above, per interface keys are only
   applicable when all the hosts reachable on the specific interface
   belong to the same security domain.

   These key types can also be used between security domains, since they
   are specific to a particular interface or neighbor.  Again, interface
   level keys can only be deployed safely when all the reachable
   neighbors on the interface belong to the same security domain.

   As discussed in Section 5.3, per neighbor and per interface keys can
   not be used in the presence of non-RSVP hops.

5.2.  Group Keys for Authentication

   Group keys apply naturally to intra-domain RSVP authentication, since
   all RSVP nodes implicitely trust each other.  Using group keys, they
   extend this trust to the group key server.  This is represented in
   Figure 1.

Behringer & Le Faucheur  Expires August 21, 2008                [Page 6]

Internet-Draft          RSVP Keying Applicability          February 2008

         :    :   :   :        :
         :    :   :   :        :
     |                                |
     |<-----domain 1----------------->|

        Figure 1: Group Key Server within a single security domain

   A single group key cannot normally be used to cover multiple security
   domains however, because by definition the different domains do not
   trust each other and would not be willing to trust the same group key
   server.  For a single group key to be used in several security
   domains, there is a need for a single group key server, which is
   trusted by both sides.  While this is theoretically possible, in
   practice it is unlikely that there is a single such entity trusted by
   both domains.  Figure 2 illustrates this setup.

         :    :   :   :        :   :   :       :
         :    :   :   :        :   :   :       :
     |                  |    |                      |
     |<-----domain 1--->|    |<-------domain 2----->|

        Figure 2: A Single Group Key Server across security domains

   A more practical approach for RSVP operation across security domains,
   is to use a separate group key server for each security domain, and
   to use per interface or per peer authentication between the two
   domains.  Figure 3 shows this set-up.

         ....GKS1......        ....GKS2.........
         :    :   :   :        :   :   :       :
         :    :   :   :        :   :   :       :
     |                  |    |                      |
     |<-----domain 1--->|    |<-------domain 2----->|

             Figure 3: A group Key Server per security domain

5.3.  Non-RSVP Hops

   In the presence of a non-RSVP router in the path from the sender to
   the receiver, regular RSVP keeps working.  The non-RSVP node ignores
   the RSVP message, and passes it on transparently to the next node.
   Figure 4 illustrates this scenario.  R2 in this picture does not
   participate in RSVP, the other nodes do.  In this case, R2 will pass

Behringer & Le Faucheur  Expires August 21, 2008                [Page 7]

Internet-Draft          RSVP Keying Applicability          February 2008

   on any RSVP messages unchanged, and will ignore them.

                      /         \
     sender----R1---R2(*)       R4----receiver
                      \         /
   (*) Non-RSVP hop

                   Figure 4: A non-RSVP Node in the path

   However, this creates an additional challenge for RSVP
   authentication.  In the presence of a non-RSVP hop, with some RSVP
   messages such as a Path message, an RSVP router does not know the
   RSVP next hop for that message at the time of forwarding it.  In
   fact, part of the role of a Path message is precisely to discover the
   RSVP next hop (and to dynamically re-discover it when it changes, say
   because of a routing change).  For example, in Figure 4, R1 knows
   that the next IP hop for a Path message addresed to the receiver is
   R2, but it does necessarily not know if the RSVP next hop is R3 or

   This means that per interface and per neighbor keys cannot easily be
   used in the presence of non-RSVP routers on the path between senders
   and receivers.

   By contrast, group keying will naturally work in the presence of non-
   RSVP routers.  Referring back to Figure 4, with group keying, R1
   would use the group key to sign a Path message addressed to the
   receiver and forwards it to R2.  Being a non-RSVP node, R2 and will
   ignore and forward the Path message to R3 or R5 depending on the
   current shortest path as determined by routing.  Whether it is R3 or
   R5, the RSVP router that receives the Path message will be able to
   authenticate it successfully with the group key.

5.4.  Subverted RSVP Nodes

   A subverted node is defined here as an untrusted node, for example
   because an intruder has gained control over it.  Since RSVP
   authentication is hop-by-hop and not end-to-end, a subverted node in
   the path breaks the chain of trust.  This is to a large extent
   independent of the type of keying used.

   For interface or per-neighbor keying, the subverted node can now
   introduce fake messages to its neighbors.  This can be used in a
   variety of ways, for example by changing the receiver address in the
   Path message, or by generating fake Path messages.  This allows path
   states to be created on every RSVP router along any arbitrary path

Behringer & Le Faucheur  Expires August 21, 2008                [Page 8]

Internet-Draft          RSVP Keying Applicability          February 2008

   through the RSVP domain.  That in itself could result in a form of
   Denial of Service by allowing exhaustion of some router resources
   (e.g. memory).  The subverted node could also generate fake Resv
   messages upstream corresponding to valid Path states.  In doing so,
   the subverted node can reserve excessive amounts of bandwidth thereby
   possibly performing a denial of service attack.

   Group keying allows the additional abuse of sending fake RSVP
   messages to any node in the RSVP domain, not just adjacent RSVP
   nodes.  However, in practice this can be achieved to a large extent
   also with per neighbor or interface keys, as discussed above.
   Therefore the impact of subverted nodes on the path is comparable,
   independently whether per-interface, per-neighbor or group keys are

5.5.  RSVP Encryption

   The keying material can also be used to encrypt the RSVP messages
   using IPsec [RFC2401], instead of, or in addition to authenticating
   them.  The same considerations apply for this case as discussed above
   for the authentication case.  Group keys are applicable only within a
   trusted domain, but they allow operation through non-RSVP speakers
   without further configuration.  Per interface or per neighbor keys
   work also inter-domain, but do not operate in the presence of a non-
   RSVP router.

   The existing GDOI standard as described in [RFC3547] contains all
   relevant policy options to allow for RSVP encryption, and no
   extensions are necessary.  An example GDOI policy would be to encrypt
   all packets of the RSVP protocol itself (IP protocol 46).  A router
   implementing GDOI is therefore automatically able to encrypt RSVP.

   [Editor's note: Applicability of tunnel vs transport mode still needs
   to be discussed.]

5.6.  RSVP Notify Messages

   [RFC3473] introduces the Notify message and allows such Notify
   messages to be sent in a non-hop-by-hop fashion.  As discussed in the
   Security Considerations section of [RFC3473], this can interfere with
   RSVP's hop-by-hop integrity and authentication model.  [RFC3473]
   describes how standard IPsec based integrity and authentication can
   be used to protect Notify messages.  We observe that, alternatively,
   in some environments, group keying may allow use of regular RSVP
   authentication ([RFC2747]) for protection of non-hop-by-hop Notify
   messages.  For example, this may be applicable to controlled
   environments where nodes invoking notification requests are known to
   belong to the same key group as nodes generating Notify messages.

Behringer & Le Faucheur  Expires August 21, 2008                [Page 9]

Internet-Draft          RSVP Keying Applicability          February 2008

6.  End Host Considerations

   Unless RSVP Proxy entities ([I-D.ietf-tsvwg-rsvp-proxy-approaches]
   are used, RSVP signaling is controlled by end systems and not
   routers.  As discussed in [RFC4230], RSVP allows both user-based
   security and host-based security.  User-based authentication aims at
   "providing policy based admission control mechanism based on user
   identities or application."  To identify the user or the application,
   a policy element called AUTH_DATA, which is contained in the
   POLICY_DATA object, is created by the RSVP daemon at the user's host
   and transmitted inside the RSVP message.  This way, a user may
   authenticate to the Policy Decision Point (or directly to the first
   hop router).  Host-based security relies on the same mechanisms as
   between routers (i.e.  INTEGRITY object ) as specified in [RFC2747].
   For host-based security, interface or neighbor based keys may be
   used, however, key management with pre-shared keys can be difficult
   in a large scale deployment, as described in section 4.  In principle
   an end host can also be part of a group key scheme, such as GDOI.  If
   the end systems are part of the same zone of trust as the network
   itself, group keying can be extended to include the end systems.  If
   the end systems and the network are in different zones of trust,
   group keying cannot be used.

7.  Applicability to Other Architectures and Protocols

   While, so far, this document only discusses RSVP security assuming
   the traditional RSVP model as defined by [RFC2205] and [RFC2747], the
   analysis is also applicable to other RSVP deployment models as well
   as to similar protocols:

   o  Aggregation of RSVP for IPv4 and IPv6 Reservations [RFC3175]: This
      scheme defines aggregation of individual RSVP reservations, and
      discusses use of RSVP authentication for the signaling messages.
      Group keying is applicable to this scheme, particularly when
      automatic Deaggregator discovery is used, since in that case, the
      Aggregator does not know ahead of time which Deaggregator will
      intercept the initial end-to-end RSVP Path message.
   o  Generic Aggregate Resource ReSerVation Protocol (RSVP)
      Reservations [RFC4860]: This document also discusses aggregation
      of individual RSVP reservations.  Here again, group keying applies
      and is mentioned in the Security Considerations section.
   o  Aggregation of Resource ReSerVation Protocol (RSVP) Reservations
      over MPLS TE/DS-TE Tunnels [RFC4804]([RFC4804]): This scheme also
      defines a form of aggregation of RSVP reservation but this time
      over MPLS TE Tunnels.  Similarly, group keying may be used in such
      an environment.

Behringer & Le Faucheur  Expires August 21, 2008               [Page 10]

Internet-Draft          RSVP Keying Applicability          February 2008

   o  Pre-Congestion Notification (PCN): [I-D.ietf-pcn-architecture]
      defines an architecture for flow admission and termination based
      on aggregated pre-congestion information.  One deployment model
      for this architecture is based on IntServ over DiffServ: the
      DiffServ region is PCN-enabled, RSVP signalling is used end-to-end
      but the PCN-domain is a single RSVP hop, i.e. only the PCN-
      boundary-nodes process RSVP messages.  In this scenario, RSVP
      authentication may be required among PCN-boundary-nodes and the
      considerations about keying approaches discussed earlier in this
      document apply.  In particular, group keying may facilitate
      operations since the ingress PCN-boundary-node does not
      necessarily know ahead of time which Egress PCN-boundary-node will
      intercept and process the initial end-to-end Path message.  Note
      that from the viewpoint of securing end-to-end RSVP, there are a
      lot of similarities in scenarios involving RSVP Aggregation over
      aggregate RSVP reservations ([RFC3175], [RFC4860]), RSVP
      Aggregation over MPLS-TE tunnels ([RFC4804]), and RSVP
      (Aggregation) over PCN ingress-egress aggregates.

8.  Security Considerations

   This entire document discusses RSVP security.

9.  Acknowledgements

   The authors would like to thank everybody who provided feedback on
   this document.  Specific thanks to Bob Briscoe, Hannes Tschofenig and
   Brian Weis.

10.  Changes to Previous Version

   The following changes were made in version 01:

10.1.  changes from behringer-00 to behringer-01

   o  New section "Applicability to Other Architectures and Protocols":
      Goal is to clarify the scope of this document: The idea presented
      here is also applicable to other architectures
      (PCN[I-D.ietf-pcn-architecture], RFC3175 and RFC4860, etc.
   o  Clarified the scope of this document versus RFC4230 (in the
      introduction, last paragraph).
   o  Added a section on "End Host Considerations".
   o  Expanded section 5.5 (RSVP Encryption) to clarify that GDOI
      contains all necessary mechanisms to do RSVP encrpytion.

Behringer & Le Faucheur  Expires August 21, 2008               [Page 11]

Internet-Draft          RSVP Keying Applicability          February 2008

   o  Tried to clarify the "trust to do what?" question raised by Bob
      Briscoe in a mail on 26 Jul 2007.  See the section on trust model.
   o  Lots of small editorial changes (references, typos, figures, etc).
   o  Added an Acknowledgements section.

10.2.  changes from behringer-01 to ietf-00

   o  various edits to make it clearer that draft-weis-gdoi-for-rsvp is
      an example of how dynamic group keying could be achieved for RSVP
      and not necessraily the recommended solution

11.  Informative References

              Eardley, P., "Pre-Congestion Notification Architecture",
              October 2007.

              Faucheur, F., Manner, J., Wing, D., and A. Guillou, "RSVP
              Proxy Approaches",
              draft-ietf-tsvwg-rsvp-proxy-approaches-03 (work in
              progress), December 2007.

              Weis, B., "Group Domain of Interpretation (GDOI) support
              for RSVP", July 2007.

   [RFC2205]  Braden, B., Zhang, L., Berson, S., Herzog, S., and S.
              Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
              Functional Specification", RFC 2205, September 1997.

   [RFC2401]  Kent, S. and R. Atkinson, "Security Architecture for the
              Internet Protocol", RFC 2401, November 1998.

   [RFC2409]  Harkins, D. and D. Carrel, "The Internet Key Exchange
              (IKE)", RFC 2409, November 1998.

   [RFC2747]  Baker, F., Lindell, B., and M. Talwar, "RSVP Cryptographic
              Authentication", RFC 2747, January 2000.

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

   [RFC3473]  Berger, L., "Generalized Multi-Protocol Label Switching
              (GMPLS) Signaling Resource ReserVation Protocol-Traffic
              Engineering (RSVP-TE) Extensions", RFC 3473, January 2003.

Behringer & Le Faucheur  Expires August 21, 2008               [Page 12]

Internet-Draft          RSVP Keying Applicability          February 2008

   [RFC3547]  Baugher, M., Weis, B., Hardjono, T., and H. Harney, "The
              Group Domain of Interpretation", RFC 3547, July 2003.

   [RFC3562]  Leech, M., "Key Management Considerations for the TCP MD5
              Signature Option", RFC 3562, July 2003.

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

   [RFC4306]  Kaufman, C., "Internet Key Exchange (IKEv2) Protocol",
              RFC 4306, December 2005.

   [RFC4804]  Le Faucheur, F., "Aggregation of Resource ReSerVation
              Protocol (RSVP) Reservations over MPLS TE/DS-TE Tunnels",
              RFC 4804, February 2007.

   [RFC4860]  Le Faucheur, F., Davie, B., Bose, P., Christou, C., and M.
              Davenport, "Generic Aggregate Resource ReSerVation
              Protocol (RSVP) Reservations", RFC 4860, May 2007.

Authors' Addresses

   Michael H. Behringer
   Cisco Systems Inc
   Village d'Entreprises Green Side
   400, Avenue Roumanille, Batiment T 3
   Biot - Sophia Antipolis  06410


   Francois Le Faucheur
   Cisco Systems Inc
   Village d'Entreprises Green Side
   400, Avenue Roumanille, Batiment T 3
   Biot - Sophia Antipolis  06410


Behringer & Le Faucheur  Expires August 21, 2008               [Page 13]

Internet-Draft          RSVP Keying Applicability          February 2008

Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
   retain all their rights.

   This document and the information contained herein are provided on an

Intellectual Property

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at


   Funding for the RFC Editor function is provided by the IETF
   Administrative Support Activity (IASA).

Behringer & Le Faucheur  Expires August 21, 2008               [Page 14]