User`s guide

Introduction
1-17
learning database to learn addresses on the incorrect ports. This
could result in frames not getting forwarded and loss of
communication.
• SRTB is a global parameter and is enabled only on Token Ring
ports with SRT bridging mode.
• The RIF database supports 8,192 entires.
• SRTB can be enabled based on IP, IPX and other protocols (SNA,
NetBIOS, etc.)
• All existing protocol translations (IP, IPX, SNA, NetBIOS and
AppleTalk) are supported when SRTB is enabled.
• The RIF caching aging timer is the same as the Spanning Tree
timer, and is configurable. The default value is 300 seconds.
• The RIF cache entry is relearned based on a separate timer that
is set to one half the Spanning Tree timer.
1.7.3 Source Routing Bridging
Source routing bridging (SR) is an alternative to transparent or
spanning tree bridging, and is widely used in Token Ring
networks. The ATX supports source routing bridging on Token
Ring LANs, and an enhancement to source routing called SRT on
all LANs.
With source routing bridging, all networked devices participate in
the source routing protocol. Each packet that crosses a bridge
specifies the originator's LAN segment, the particular bridge, and
the destination LAN segment. It may also specify intermediate
LAN segments and bridges.