17-37
Ethernet Card Software Feature and Configuration Guide, R7.2
January 2009
Chapter 17 Configuring Cisco Proprietary Resilient Packet Ring
Understanding Redundant Interconnect
Understanding Redundant Interconnect
Ring interconnect (RI) is a mechanism to interconnect RPRs, both RPR-IEEE and Cisco proprietary
RPR, for protection from failure. It does this through redundant pairs of back-to-back G igabit Ethernet
connections that bridge RPR networks. One connection is the active node and the other is the standby
node. During a failure of the active node, link, or card, the detection of the failure triggers a switchover
to the standby node. Figure 17-15 illustrates an example of RPR RI.
Figure 17-15 RPR RI

Characteristics of RI on the ML-Series Card

RI on the ML-Series card has these characteristics:
Supported only on Gigabit Ethernet
Provisioned by identifying peer RPR MACs as either primary or standby
Uses an OAM frame to flush the spatially aware sublayer (SAS) table and MAC table at the add
stations
Provides protection between individual RPRs, including:
Two RP Rs
Two Cisco proprietary RPRs
A Cisco proprietary ring and an IEEE 802.17 ring
GEC
151968
Primary
pair
A
ML1000-2
West East
B
ML1000-2
West East
C
ML1000-2
West East
D
ML1000-2
West East
OC-N
OC-N
Secondary
pair