Brocade Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide (Supporting R05.6.00) - Manual (Page 331)

Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide 307
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LDP outbound FEC filtering
2
3 10.66.66.66/32 Installed
Upstream label database:
Label Prefix
3 10.44.44.44/32
1024 172.16.8.0/24
1025 172.16.16.0/24
1026 172.16.32.0/24
1027 172.16.64.0/24
1028 172.16.8.0/28
1029 172.16.8.16/28
1030 172.16.8.32/28
1031 172.16.8.64/28
1032 10.14.14.14/32
LDP outbound FEC filtering
LDP performs a hop-by-hop or dynamic path setup in an MPLS network by assigning and
distributing labels to routes learned from the underlying IGP routing protocols. By default, LDP
distributes all FECs learned locally or from LDP neighbors, to all other LDP neighbors. When this is
not desired, you can configure LDP to perform outbound filtering for label advertisement using the
outbound fec filtering feature. This is achieved by creating a prefix-list specifying prefixes whose
label mappings can be distributed. The prefix-list is then applied to an individual LDP neighbor, or
globally to all the LDP neighbors. The FECs permitted by the prefix-list only are accordingly
distributed to the specified LDP neighbor or to all LDP neighbors.
This feature gives you the ability to control which FECs can be advertised and to which LDP
neighbors.
• This feature reduces the number of Labels distributed to neighbors and the number of
messages exchanged with peers.
• Improves LDP scalability and convergence.
• Improves security and performance.
Limitations and pre-requisites
MPLS and LDP protocol must be enabled on the router to use this feature.
Upgrade and downgrade considerations
On Upgrade, because there is no outbound fec filter configured, all FEC are allowed by default. For
downgrade, value of outbound "fec-filter" configured, if any, is lost.
Backward compatibility
The feature supports only the Multi-Service NetIron Release 05.600 onwards and does not cause
any incompatibility with older releases. It is fully backward compatible.