3Com MSR 50 Series Configuration Manual page 407

When Host B responds to Host B, the bridge also hears the Ethernet frame from
Host B. As the frame is received on bridge interface 1, the bridge determines that
Host B is also attached to bridge interface 1, and creates a mapping between the
MAC address of Host B and bridge interface 1 in its bridge table, as shown in
Figure 107.
Figure 107 The bridge determines that Host B is also attached to interface 1
MAC address : 00 e0.fcaa .aaaa
Host A
Bridge table
MAC address
00e 0. fcaa.aaaa
00e 0. fcbb.bbbb
Host C
MAC address : 00 e0.fccc .cccc
Finally, the bridge obtains all the MAC-interface mappings (assume that all hosts
are in use), as shown in
Figure 108 The final bridge table
MAC address : 00 e0.fcaa .aaaa
Host A
Bridge table
MAC address
00 e0.fcaa .aaaa
00 e0.fcbb .bbbb
00 e0.fccc.cccc
00 e0.fcdd .dddd
Host C
MAC address : 00 e0.fccc .cccc
Source address
00 e0.fcbb . bbbb
Interface
Bridge interface 1
1
Bridge
1
Bridge interface 2
Figure 108.
Interface
Bridge interface 1
1
Bridge
1
2
Bridge interface 2
2
Bridging Overview 407
MAC address: 00e0.fcbb .bbbb
Host B
Destination address
00e0.fcaa . aaaa
LAN segment 1
LAN segment 2
Host D
MAC address: 00e0.fcdd .dddd
MAC address : 00e0.fcbb .bbbb
Host B
LAN segment 1
LAN segment 2
Host D
MAC address : 00e0.fcdd .dddd