Lucent Technologies 6000 - Manual (Page 524)

14-4 MAX 6000/3000 Network Configuration Guide
Configuring Packet Bridging
How the MAX supports bridging
in promiscuous mode incurs greater processor and memory overhead than the standard mode
of operation for the Ethernet controller.)
You enable packet bridging by opening Ethernet > Mod Config and setting the Bridging
parameter to Yes:
Ethernet
Mod Config
Bridging=Yes
How the MAX supports bridging
To forward bridged packets to the correct destination network, the MAX uses a bridge table
that associates end nodes with particular connections. It builds this table dynamically
(transparent bridging). It also incorporates the entries found in its Bridge Adrs profiles. Bridge
Adrs profiles are analogous to static routes in a routing environment. You can define up to 99
destination nodes and their connection information in Bridge Adrs profiles.
Transparent bridging
As a transparent bridge (also termed a learning bridge), a MAX unit keeps track of the location
of a particular address, and of the Connection profile that specifies the interface to which the
packet should be forwarded. When forwarding a packet, the unit logs the packet’s source
address and creates a bridge table that associates node addresses with a particular interface.
For example, Figure 14-2 shows the physical addresses of some nodes on the local Ethernet
network and at a remote site. The MAX unit at Site A has a bridge configuration.
Figure 14-2. How the MAX creates a bridging table
The MAX unit at Site A gradually learns addresses on both networks by looking at each
packet’s source address, and it develops a bridge table that includes the following entries:
0000D801CFF2 SITEA
080045CFA123 SITEA
08002B25CC11 SITEA
08009FA2A3CA SITEB
Entries in the unit’s bridge table must be relearned within a fixed aging limit, or they are
removed from the table.
Ethernet
MAX MAX
Site B Site A
0000D801CFF2
080045CFA123
08002B25CC11
08009FA2A3CA
WAN