RFC 3210 (rfc3210) - Page 2 of 8
Applicability Statement for Extensions to RSVP for LSP-Tunnels
Alternative Format: Original Text Document
RFC 3210 Applicability Statement for Extensions December 2001
submitted to the IETF MPLS working group. It contains all the
necessary objects, packet formats, and procedures required to
establish and maintain explicit label switched paths (LSPs).
Explicit LSPs are foundational to the traffic engineering application
in MPLS based IP networks. Besides the traffic engineering
application, the RSVP-TE specification may have other uses within the
Internet.
This memo describes the applicability of the RSVP-TE specifications
[1]. The protocol's principles of operation are highlighted, the
network context for which it was developed is described, guidelines
for deployment are offered, and known protocol limitations are
indicated.
This applicability statement concerns only the use of RSVP to set up
unicast LSP-tunnels. It is noted that not all of the features
described in RFC 2205 [3] are required to support the instantiation
and maintenance of LSP-tunnels. Aspects related to the support of
other features and capabilities of RSVP by an implementation that
also supports LSP-tunnels are beyond the scope of this document.
However, support of such additional features and capabilities should
not introduce new security vulnerabilities in environments that only
use RSVP to set up LSP-tunnels.
This applicability statement does not preclude the use of other
signaling and label distribution protocols for the traffic
engineering application in MPLS based networks. Service providers
are free to deploy whatever signaling protocol that meets their
needs.
In particular, CR-LDP [6] and RSVP-TE [1] are two signaling protocols
that perform similar functions in MPLS networks. There is currently
no consensus on which protocol is technically superior. Therefore,
network administrators should make a choice between the two based
upon their needs and particular situation.
2.0 Technical Overview of Extensions to RSVP for LSP Tunnels
The RSVP-TE specification extends the original RSVP protocol by
giving it new capabilities that support the following functions in an
MPLS domain:
(1) downstream-on-demand label distribution
(2) instantiation of explicit label switched paths
(3) allocation of network resources (e.g., bandwidth) to
explicit LSPs
(4) rerouting of established LSP-tunnels in a smooth fashion
using the concept of make-before-break
Awduche, et. al. Informational