Network Working Group M. Behringer
Internet-Draft F. Le Faucheur
Intended status: Informational Cisco Systems Inc
Expires: January 12, 2009 July 11, 2008
Applicability of Keying Methods for RSVP Security
draft-ietf-tsvwg-rsvp-security-groupkeying-01.txt
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Abstract
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. For example, the Group Domain of Interpretation
(GDOI) could be used to distribute group keys to RSVP nodes. The
present document also discusses applicability of group keying to RSVP
encryption.
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Table of Contents
1. Introduction and Problem Statement . . . . . . . . . . . . . . 3
2. The RSVP Hop-by-Hop Trust Model . . . . . . . . . . . . . . . 3
3. Applicability of Key Types for RSVP . . . . . . . . . . . . . 5
3.1. Interface and neighbor based keys . . . . . . . . . . . . 5
3.2. Group keys . . . . . . . . . . . . . . . . . . . . . . . . 6
4. Key Provisioning Methods for RSVP . . . . . . . . . . . . . . 7
4.1. Static Key Provisioning . . . . . . . . . . . . . . . . . 7
4.2. Dynamic Keying . . . . . . . . . . . . . . . . . . . . . . 8
4.2.1. Neighbor and Interface Based Key Negotiation . . . . . 8
4.2.2. Dynamic Group Key Distribution . . . . . . . . . . . . 8
5. Specific Cases . . . . . . . . . . . . . . . . . . . . . . . . 8
5.1. RSVP Notify Messages . . . . . . . . . . . . . . . . . . . 8
5.2. RSVP-TE . . . . . . . . . . . . . . . . . . . . . . . . . 9
6. Applicability of IPsec for RSVP . . . . . . . . . . . . . . . 9
6.1. Applicability of IPsec ESP . . . . . . . . . . . . . . . . 10
6.2. Applicability of Tunnel Mode . . . . . . . . . . . . . . . 10
6.3. Applicability of Transport Mode . . . . . . . . . . . . . 11
7. End Host Considerations . . . . . . . . . . . . . . . . . . . 11
8. Applicability to Other Architectures and Protocols . . . . . . 11
9. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
10. Security Considerations . . . . . . . . . . . . . . . . . . . 13
10.1. Subverted RSVP Nodes . . . . . . . . . . . . . . . . . . . 13
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14
12. Changes to Previous Version . . . . . . . . . . . . . . . . . 14
12.1. changes from behringer-00 to behringer-01 . . . . . . . . 14
12.2. changes from behringer-01 to ietf-00 . . . . . . . . . . . 14
12.3. changes from ietf-00 to ietf-01 . . . . . . . . . . . . . 15
13. Informative References . . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
Intellectual Property and Copyright Statements . . . . . . . . . . 18
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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 RSVP
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-mac-tek] 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 Hop-by-Hop 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.
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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-mac-tek]).
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 or
encryption 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. 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, for example because of a routing change). Thus, the
presence of non-RSVP hops impacts operation of RSVP authentication or
encryption and may influence the selection of keying approaches.
Figure 1 illustrates this scenario. R2 in this picture does not
participate in RSVP, the other nodes do. In this case, R2 will pass
on any RSVP messages unchanged, and will ignore them.
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----R3---
/ \
sender----R1---R2(*) R4----receiver
\ /
----R5---
(*) Non-RSVP hop
Figure 1: A non-RSVP Node in the path
This creates a challenge for RSVP authentication and encrpytion. 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. For example, in Figure 1, 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 R5.
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 1, 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.
3. Applicability of Key Types for RSVP
3.1. Interface and neighbor 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 equivalent 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
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
required.
With neighbor based keys, an RSVP key is bound to an interface plus a
neighbor on that interface. It allows the distinction of different
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trust groups on a single subnet. (Assuming that layer-2 security is
correctly implemented to prevent layer-2 attacks.)
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 nodes 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 the previous section, per neighbor and per interface
keys can not be used in the presence of non-RSVP hops.
3.2. 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 within the group).
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 2.
......GKS1.............
: : : : :
: : : : :
source--R1--R2--R3-----destination
| |
|<-----domain 1----------------->|
Figure 2: 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 3 illustrates this setup.
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...............GKS1....................
: : : : : : : :
: : : : : : : :
source--R1--R2--R3--------R4--R5--R6--destination
| | | |
|<-----domain 1--->| |<-------domain 2----->|
Figure 3: 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 neighbor authentication between the two
domains. Figure 4 shows this set-up.
....GKS1...... ....GKS2.........
: : : : : : : :
: : : : : : : :
source--R1--R2--R3--------R4--R5--R6--destination
| | | |
|<-----domain 1--->| |<-------domain 2----->|
Figure 4: A group Key Server per security domain
As discussed in section 2, group keying can be used in the presence
of non-RSVP hops.
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
network.
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
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infrastructure trusted by both domains to update keys on both sides.
Thus, manually configured keys may be applicable to inter-domain RSVP
authentication.
Since it is not feasible to carry out the key change at the exact
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. (Note that
also with dynamic keying approaches there can be a grace period where
two keys are valid at the same time; however, the grace period in
manual keying tends to be significantly longer than with dynamic key
rollover schemes.)
4.2. Dynamic Keying
4.2.1. Neighbor and Interface Based Key Negotiation
To avoid the problem of manual key provisioning and updates in static
key deployments, key negotiation between RSVP neighbors 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.
4.2.2. Dynamic Group Key Distribution
With this approach, group keys are dyanmically distributed among a
set of RSVP routers. For example, [I-D.weis-gdoi-mac-tek] 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. Specific Cases
5.1. 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
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belong to the same key group as nodes generating Notify messages.
5.2. RSVP-TE
Use of RSVP authentication for RSVP-TE [RFC3209] and for RSVP-TE Fast
Reroute [RFC4090] deserve additional considerations. For example,
with the facility backup method of Fast Reroute, a backup tunnel from
the Point of Local Repair (PLR) to the Merge Point (MP) is used to
protect Label Switched Paths (protected LSPs) from the failure of a
facility (e.g. a router) located between the PLR and the MP. During
the failure of the facility, the PLR redirects a protected LSP inside
the backup tunnel and also exchange RSVP control message for the
maintenance the protected LSP over the backup tunnel. Therefore,
during the rerouted period, the PLR and the MP effectively become
RSVP neighbors while they may not be directly connected to each other
and thus do not behave as RSVP neighbors in the absence of failure.
This point is raised in the Security Considerations section of
[RFC4090] that says: "Note that the facility backup method requires
that a PLR and its selected merge point trust RSVP messages received
from each other." We observe that such environments may benefit from
group keying since the group key could also be easily used between
the PLR and the MP.
6. Applicability of IPsec for RSVP
The discussions about the various keying methods in this document are
applicable to the built-in authentication in the RSVP protocol, using
the INTEGRITY object, as defined in [RFC2747]. In principle, they
are also applicable to using IPsec to protect RSVP, however,
[RFC2747] discusses in section 1.2 why IPsec is not an optimal choice
to protect RSVP. The key argument is that an IPsec SA and an RSVP SA
are not based on the same parameters. We believe that group keying
may solve some of the issues mentioned. [Editorial note: Detailed
discussion will be added in the next version of the document.]
To address specific requirements for RSVP encryption, we focus the
discussion here on IPsec ESP (Encapsulation security payload;
[RFC4303]).
IPsec Authentication Header (AH) is currently not considered in this
document, since authentication is built into RSVP through the
mechansims defined by [RFC2747].
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6.1. Applicability of IPsec ESP
The keying approaches discussed in this document can also be used to
encrypt the RSVP messages using IPsec [RFC4301], 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 and IPsec is therefore able to implement RSVP
encryption.
Since in both tunnel mode and transport mode ESP does not protect the
header (in tunnel mode the outer header), there is an issue with
group keying, when using ESP to secure the RSVP packets: The packet
header could be modified by a man-in-the-middle attack, replacing the
destination address with another RSVP router in the network. This
router will receive the packet, use the group key to decrypt the
encapsulated packet, and then act on the RSVP packet. This way an
attacker cannot create new reservations or affect existing ones, but
he can "re-direct" reservations to parts of the network off the
actual reservation path, thereby potentially denying resources to
other applications on that part of the network.
6.2. Applicability of Tunnel Mode
IPsec tunnel mode for ESP encapsulates and encypts the original
packet, prepending a new IP tunnel header plus an ESP sub-header.
The entire original packet is encrypted, and the integrity of the
original packet plus the ESP subheader is secured. The new, outer IP
header however is not cryptographically secured in this process.
Protecting RSVP packets with IPsec ESP tunnel mode works with any of
the above described keying methods (interface, neighbor or group
based), as long as there are no non-RSVP nodes on the path. Note
that for RSVP messages to be visible and considered at each hop, such
a tunnel would not cross routers, but each RSVP node would establish
a tunnel with each of its peers, effectively leading to link
protection.
In the presence of a non-RSVP hop, tunnel mode can not be applied,
because a router upstream a non-RSVP hop does not know the next RSVP
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hop, and can thus not apply the correct tunnel header. This is
independent of the key type used.
6.3. Applicability of Transport Mode
IPsec transport mode for ESP, as defined in [RFC4303] is not suitable
for securing RSVP Path messages, since those messages preserve the
original source and destination. [RFC4303] states explicitely that
"the use of transport mode by an intermediate system (e.g., a
security gateway) is permitted only when applied to packets whose
source address (for outbound packets) or destination address (for
inbound packets) is an address belonging to the intermediate system
itself. This would not be the case for RSVP Path messages.
7. 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.
8. 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:
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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.
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.
9. Summary
The following table summarizes the various approaches for RSVP
keying, and their applicability to various RSVP scenarios. In
particular, such keying can be used for RSVP Authentication and/ or
for RSVP Encryption (using ESP in Tunnel mode).
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+-----------------------------+--------------------+----------------+
| | Neighbor/interface | Group keys |
| | based keys | |
+-----------------------------+--------------------+----------------+
| Works intra-domain | Yes | Yes |
| Works inter-domain | Yes | No |
| Works over non-RSVP hops | No | Yes (1) |
| Dynamic keying | Yes (IKE) | Yes (eg GDOI) |
+-----------------------------+--------------------+----------------+
Table 1: Overview of keying approaches and their applicability
(1): RSVP authentication with group keys works over non-RSVP nodes;
RSVP encryption with IPsec ESP Tunnel mode does not.
We also make the following observations:
o All key types can be used statically, or with dynamic key
negotiation. This impacts the managability of the solution, but
not the applicability itself.
o For encryption of RSVP messages IPsec ESP in tunnel mode can be
used. There is however a security concern, see Section 6.1.
o There are some special cases in RSVP, like non-RSVP hosts, the
"notify" message, the various RSVP deployment models discussed in
Section 8 and MPLS traffic engineering, which would benefit from a
group keying approach.
10. Security Considerations
This entire document discusses RSVP security; this section describes
a specific security considerations relating to subverted RSVP nodes
10.1. 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
through the RSVP domain. That in itself could result in a form of
Denial of Service by allowing exhaustion of some router resources
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(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
used.
11. Acknowledgements
The authors would like to thank everybody who provided feedback on
this document. Specific thanks to Bob Briscoe, Hannes Tschofenig and
Brian Weis.
12. Changes to Previous Version
This section provides a change log. It will be removed in the final
document:
12.1. 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.
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.
12.2. 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 necesarily the recommended solution
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12.3. changes from ietf-00 to ietf-01
o Significant re-structuring of the entire document, to improve the
flow, and provide more consistency in various sections.
o Moved the "Subverted RSVP nodes" discussion into the security
considerations section.
o Added a "summary" section.
o Complete re-write of the old section 5.5 (RSVP encryption), and
"promotion" to a separate section.
o Changed reference ID.weis-gdoi-for-rsvp to the new draft ID.weis-
gdoi-mac-tek
o in several places, explicitely mentioned "encryption" for RSVP (in
parallel to authentication).
o Various minor edits.
13. Informative References
[I-D.ietf-pcn-architecture]
Eardley, P., "Pre-Congestion Notification Architecture",
draft-ietf-pcn-architecture-03 (work in progress),
February 2008.
[I-D.ietf-tsvwg-rsvp-proxy-approaches]
Faucheur, F., Manner, J., Wing, D., and A. Guillou, "RSVP
Proxy Approaches",
draft-ietf-tsvwg-rsvp-proxy-approaches-04 (work in
progress), April 2008.
[I-D.weis-gdoi-mac-tek]
Weis, B. and S. Rowles, "GDOI Generic Message
Authentication Code Policy", draft-weis-gdoi-mac-tek-00
(work in progress), July 2008.
[RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, September 1997.
[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.
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Internet-Draft RSVP Keying Applicability July 2008
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, December 2001.
[RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Resource ReserVation Protocol-Traffic
Engineering (RSVP-TE) Extensions", RFC 3473, January 2003.
[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.
[RFC4090] Pan, P., Swallow, G., and A. Atlas, "Fast Reroute
Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
May 2005.
[RFC4230] Tschofenig, H. and R. Graveman, "RSVP Security
Properties", RFC 4230, December 2005.
[RFC4301] Kent, S. and K. Seo, "Security Architecture for the
Internet Protocol", RFC 4301, December 2005.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, 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.
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Authors' Addresses
Michael H. Behringer
Cisco Systems Inc
Village d'Entreprises Green Side
400, Avenue Roumanille, Batiment T 3
Biot - Sophia Antipolis 06410
France
Email: mbehring@cisco.com
URI: http://www.cisco.com
Francois Le Faucheur
Cisco Systems Inc
Village d'Entreprises Green Side
400, Avenue Roumanille, Batiment T 3
Biot - Sophia Antipolis 06410
France
Email: flefauch@cisco.com
URI: http://www.cisco.com
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Behringer & Le Faucheur Expires January 12, 2009 [Page 18]
