Unknown&Broadcast Forwarding
DeÞnes how frames destined for unknown destination addresses (not in the bridge database) and broadcast destination addresses are handled when the frame is transmitted by the Token Ring interfaces. This Þeld is per bridge interface.
¥For the FDDI interface, the frame cannot be changed. It is Þxed as a transparent only (TP) network. Therefore, all unknown and broadcast frames are sent onto FDDI as TP frames.
¥For the Token Ring interfaces, this Þeld is selectable. Table 3 describes what choices are available and when.
Table 3. Unknown and Broadcast Forwarding Choices
Bridge Method | Unknown & Broadcast Forwarding Choices |
|
|
|
|
| TP - Frames that are destined for an unknown destination |
| address (not in bridge database) or a broadcast destination |
TP | address are forwarded on to the Token Ring(s) as TP frames. |
| No translation for source routing is performed. |
|
|
| ARE - Frames that are destined for an unknown destination |
| address (not in bridge database) or a broadcast destination |
| address are forwarded onto the Token Ring(s) as All Route |
| Explorer (ARE) frames. FDDI TP frames are translated to |
| this type of source routed frame. |
SR | STE - Frames that are destined for an unknown destination |
| address (not in bridge database) or a broadcast destination |
| address are forwarded onto the Token Ring(s) as Spanning |
| Tree Explorer (STE) frames. FDDI TP frames are translated |
| to this type of source routed frame. |
|
|
| ARE (See ARE deÞnition above) |
SRT (default) | STE (See STE deÞnition above). This is the default. |
| TP (See TP deÞnition above) |
|
|
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