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Operation Manual – MPLS TE
H3C S9500 Series Routing Switches
Chapter 1 MPLS TE Configuration
1-6
V. Administrative group and affinity attribute
The affinity attribute of an MPLS TE tunnel identifies the properties of the links that the
tunnel can use. Together with the link administrative group, it decides which links the
MPLS TE tunnel can use.
VI. Reoptimization
Traffic engineering is a process of allocating/reallocating network resources. You may
configure it to meet desired QoS.
Normally, service providers use some mechanism to optimize CR-LSPs for best use of
network resources. They can do this manually but CR-LSP measurement and tuning
are required. Alternatively, they can use MPLS TE where CR-LSPs are dynamically
optimized.
Dynamic CR-LSP optimization involves periodic calculation of paths that traffic trunks
should traverse. If a better route is found for an existing CR-LSP, a new CR-LSP will be
established to replace the old one, and services will be switched to the new CR-LSP.
1.1.5 CR-LDP
Constraint-based routed label distribution protocol (CR-LDP) is an extension to LDP. It
is used in MPLS TE to create an explicit path with resource reservation between the
ingress node and the egress node.
When initiating an LSP at the ingress, CR-LDP appends some constraints in the label
request message.
Note:
The S9500 series does not support CR-LDP.
1.1.6 RSVP-TE
This section covers these topics:
z
Overview
z
Basic concepts of RSVP-TE
z
Make-before-break
z
RSVP-TE messages
z
Setting up an LSP tunnel
z
RSVP refresh mechanism
z
PSB, RSB and BSB timeouts