274
Figure 283 The bridge determines that Host B is also attached to interface 1
Finally, the bridge obtains all the MAC-interface mappings (assume that all hosts are in use), as shown
in Figure 284.
Figure 284 The final bridge table
Forwarding and filtering
The bridge makes data forwarding or filtering decisions based on the following scenarios:
• When Host A sends an Ethernet frame to Host C, the bridge searches its bridge table and finds out
that Host C is attached to bridging interface 2, and forwards the Ethernet frame out of bridging
interface 2, as shown in Figure 285.
Host A
Host B
Host C Host D
LAN segment 2
LAN segment 1
Bridge
Bridge interface 1
Bridge interface 2
00e0.fcbb.bbbb 00e0.fcaa.aaaa
Source address Destination address
00e0.fcbb.bbbb 1
00e0.fcaa.aaaa 1
MAC address Interface
Bridge table
MAC address: 00e0.fcaa.aaaa
MAC address: 00e0.fccc.cccc
MAC address: 00e0.fcdd.dddd
MAC address: 00e0.fcbb.bbbb
MAC address: 00e0.fccc.cccc
Host A
Host B
Host C Host D
LAN segment 2
LAN segment 1
Bridge interface 1
00e0.fcbb.bbbb 1
00e0.fccc.cccc 2
00e0.fcaa.aaaa 1
00e0.fcdd.dddd 2
MAC address Interface
Bridge table
MAC address: 00e0.fcaa.aaaa
MAC address: 00e0.fcdd.dddd
MAC address: 00e0.fcbb.bbbb
Bridge interface 2
Bridge