HP 200 Series Services And Applications page 80

Bridging Service
Source-Routing Bridging
Track 1. An Explorer Frame From Node 1 to Node 2
This section tracks explorer frames (AREs) sent from H1 to H2 in the
sample HP source-routing bridging network. Figure 18 below illustrates the
same network as does figure 17, except that arrows in figure 18 indicate the
direction of the frame's path.
1
H1
Figure 18. Tracking an Explorer Frame
First bridge receiving the explorer frame:
received by bridge A from ring 1 has not traversed any other bridges.
A simply does the following to the RIF before transmitting the frame
toward ring 2. (Figure 19 illustrates the RIF in the frame.)
Adds the incoming LAN ID, and its bridge ID
Adds the internal LAN ID, and its bridge ID
Adds the outgoing LAN ID, and bridge ID of 0
Other bridges receiving the explorer frame:
received by bridges B and C contains internal LAN IDs (thus indicating
that this frame has traversed at least one other bridge). Each of these
bridges does the following to the RIF before transmitting the frame
toward rings 3 and 4. (Figure 19 illustrates the RIF in the frame.)
Keeps the outgoing LAN ID as its incoming LAN ID; replaces the
bridge ID of 0 with its own bridge ID.
Replaces the internal LAN ID and bridge ID of the last bridge
traversed with its own internal LAN ID and bridge ID.
Adds the outgoing LAN ID, and bridge ID of 0.
2-28
2
router A router B
Internal LAN ID = 100 Internal LAN ID = 101
Group LAN ID = FFF Group LAN ID = FFF
Bridge ID = A Bridge ID = A
4
3
router C
Internal LAN ID = 102
Group LAN ID = FFF
Bridge ID = A
The explorer frame
The explorer frame
H2