3Com 3C13636 Configuration Manual page 353

3Com Router 3000 Ethernet Family
Configuration Guide
00e0.fcaa.aaaa
00e0.fccc.cccc
Figure 3-4 Final bridging address table
II. Forward and Filter
The bridge will make the decision to forward frames or not (that is, to filter frames)
depending on the following three conditions:
If Workstation A sends an Ethernet frame whose destination is Workstation C,
the bridge will detect this frame and learn that Workstation C corresponds to
Bridge port 2 by looking up its bridging table. So, it will forward the frame to
Bridge port 2, as shown in the following figure.
00e0.fcaa.aaaa
00e0.fccc.cccc
Figure 3-5 Forward
Workstation A
Bridging table
MAC address
Port
00e0.fcaa.aaaa
1
00e0.fcbb.bbbb 1
00e0.fccc.cccc 2
00e0.fcdd.dddd 2
Bridge
Workstation C
Workstation A
Source address Destination address
00e0.fcaa.aaaa 00e0.fccc.cccc
Bridging table
MAC address
Port
00e0.fcaa.aaaa
1
00e0.fcbb.bbbb 1
00e0.fccc.cccc 2
00e0.fcdd.dddd 2
Workstation C
Destination address Source address
00e0.fccc.cccc 00e0.fcaa.aaaa
3Com Corporation
00e0.fcbb.bbbb
Bridge port 1
Bridge port 2
00e0.fcbb.bbbb
Bridge port 1
00e0.fcdd.dddd
Bridge
Forwarding
Bridge port 2
3-4
Chapter 3 Bridge Configuration
Workstation B
Ethernet segment 1
00e0.fcdd.dddd
Workstation D
Ethernet segment 2
Workstation B
Ethernet segment 1
Workstation D
Ethernet segment 2