Brocade Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide (Supporting R05.6.00) - Manual (Page 167)

Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide 143
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Link protection for FRR
1
Node Protection: In this protection, backup is selected in such a way that it avoids the failed link
along with router to which this link connects to. The node which was responsible for link failure, is
avoided altogether in its entirety, which was used earlier by the LSP. Traffic merges back to main
stream from backup on somewhere downstream from the node, which is being avoided. Refer to
Figure 22 illustrating node protection provided at R1 to LSP ingressing from R1 to R4.
FIGURE 22 Node protection
Through Multi-Service NetIron Release 05.500, Brocade’s NetIron routers pose default behavior
with request of “Node Protection Desired” whenever local protection is requested for RSVP LSPs. It
is not possible to request link protection over node protection or vice versa.
As part of this feature, ingress routers are allowed to expose this property of MPLS RSVP LSP to you
and lets the user choose or prefer between Link protection or Node protection. Once the Node
protection is chosen, PLR first tries to establish a backup LSP which provides Node protection.
When Node Protection is not possible, it attempts to fall back to Link protection.
When the user chooses link protection over node protection, this is communicated to all routers
participating in LSP. Each PLR in this case limits its search for backup LSP which provides link
protection. In cases where link protection cannot be offered, PLR falls back to node protection.
The above feature is applicable to both one to one protection and many to one FRR protection.
The feature provides options to the user to set preferential method requested for local protection.
When RSVP LSP is enabled with FRR (local protection), the user would be able to configure either
Link protection or Node protection. Node protection remains the default.
Configuration steps for adaptive and non-adaptive LSPs have inherent differences with respect to
their make-before break capabilities. The default behavior for both type of LSPs remains node
protection.
Configuring protection type preference for Non-Adaptive LSPs
You are able to change protection type preference (Node protection to Link protection or vice versa)
only on admin down state of a non-adaptive LSPs. Any non-adaptive LSP which is already enabled
by the user for signaling, cannot be changed.