Cisco CRS Configuration Guide

Policy-Based Tunnel Selection 186
Policy-Based Tunnel Selection Functions 187
PBTS Restrictions 187
Path Protection 188
Pre-requisites for Path Protection 188
Restrictions for Path Protection 189
Restrictions for Explicit Path Protection 189
Co-existence of Path Protection with Fast Reroute 190
MPLS-TE Automatic Bandwidth 190
MPLS-TE Automatic Bandwidth Overview 190
Adjustment Threshold 192
Overflow Detection 192
Underflow Detection 192
Restrictions for MPLS-TE Automatic Bandwidth 193
Point-to-Multipoint Traffic-Engineering 193
Point-to-Multipoint Traffic-Engineering Overview 193
Point-to-Multipoint RSVP-TE 195
Point-to-Multipoint Fast Reroute 196
Point-to-Multipoint Label Switch Path 196
Path Option for Point-to-Multipoint RSVP-TE 196
MPLS Traffic Engineering Shared Risk Link Groups 198
Explicit Path 199
Fast ReRoute with SRLG Constraints 199
Importance of Protection 201
Delivery of Packets During a Failure 202
Multiple Backup Tunnels Protecting the Same Interface 202
SRLG Limitations 202
MPLS TE SRLG Scale Enhancements 203
Soft-Preemption 203
Path Option Attributes 204
Configuration Hierarchy of Path Option Attributes 204
Traffic Engineering Bandwidth and Bandwidth Pools 205
Path Option Switchover 205
Path Option and Path Protection 206
Auto-Tunnel Mesh 206
Cisco IOS XR MPLS Configuration Guide for the Cisco CRS Router, Release 5.1.x
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Contents

Cisco CRS Specifications

General

Operating System	Cisco IOS XR
Product Type	Core Router
Form Factor	Modular Chassis
Dimensions	Varies by chassis type
Weight	Varies by chassis type
Architecture	Distributed
Switch Fabric	Multi-stage
Interface Support	Ethernet, SONET/SDH, OTN
Interfaces/Ports	Varies by line card
Port Density	Varies by line card
Routing Protocol	BGP, IS-IS, OSPF, MPLS
Management	CLI, SNMP
Power Supply	Redundant, hot-swappable
Cooling	Redundant, Hot-swappable Fan Trays
Supported Protocols	IPv4, IPv6, MPLS
Management Interfaces	Ethernet, console
Security Features	ACLs