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SSIM-H2-02 Fast Ethernet - Translational Switch SmartStack Interface Module Installation and User Guide Configuration
Bridging Modes

Source Routed Switching (SRS) Operation Mode

SRS is the default mode of operation. This mode is also restored after NVRAM
reset of the SmartStack STS16-20RM switch. In this mode, all ports of the switch
are in the same CRF (including SmartStack SSIM-H2-02 switch ports). Frames are
switched between ports based only on MAC addresses. In this mode, by default the
spanning tree algorithm is disabled. If more than one translational link is used to
connect to the Ethernet cloud, IEEE spanning tree on the CRF should be enabled.

Source Routed Transparent Bridging (SRT) Mode

➽Note: SRT is the suggested mode of operation.
If multiple CRFs are used on a switch, all translational links to the same Ethernet
cloud should be grouped into one CRF. If spanning tree is to be used, enable STP
on the CRF and BRF. The CRF’s STP should be set to IEEE; the BRFs’ STP should
be set to Based on Bridging mode or IEEE. (For more information, see the
SmartStack STS16-20RM/STS16-20FRM Token Ring Switch Installation and User
Guide.)
Note that this translational CRF is used only on the Token Ring side and is used
toroute source-routed Token Ring frames toward the Ethernet cloud.
Figure 4. Ethernet CRF in SRT Bridging Mode