Dynamic Source Route Recovery; Figure 9. Example Of Dynamic Source Route Recovery, Base Configuration - Cabletron Systems SmartSTACK STS16-20RM Installation And User Manual

Dynamic Source Route Recovery

Dynamic Source Route Recovery (DSRR) is a proprietary protocol that enables a
group of switches to handle a link or switch failure without session loss.
A basic redundant setup must have a minimum of two switches performing source
route bridging between a legacy Token-Ring and an emulated Token-Ring (or
another legacy ring) as illustrated in Figure 9.

Figure 9. Example of Dynamic Source Route Recovery, Base Configuration

This configuration already has redundant paths between the two rings, but since
moving traffic from one path to the other involves changing source route, this
would involve session loss.
When DSRR is enabled, an extra path is automatically created between the two
rings for each switch, as shown in Figure 10. During normal operation, these extra
paths do not forward any traffic.
Switch Overview
BRF
Bridge No. B1
CRF
BRF
Bridge No. B2
CRF
SmartStack STS16-20RM/STS16-20FRM Token Ring Switches, P/N: 9032957-01
CRF
A
T
M
CRF
A
T
M
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