Cabletron Systems SSR-ATM29-02, User Manual, Page: 64 / 386

Chapter 6: Configuring SSR Bridging
64 CoreWatch User’s Guide
Configuring the Bridging Mode of Ports
You can configure ports to use either of the following bridging modes. Each port has a
Layer-2 lookup table where MAC address or flows are stored. A port’s bridging mode
determines the contents of each Layer-2 table entry. A port can use only one type of
bridging at a time.
• Flow-based bridging
If a port is configured for flow-based bridging, each Layer-2 table entry contains
entries consisting of a source MAC address, destination MAC address, and VLAN ID.
• Address-based bridging
If a port is configured for address-based bridging (the default), each Layer-2 table entry
contains a unique destination MAC address and VLAN ID.
Suppose that a port on the SSR is connected to a hub that is connected to three
workstations, A, B, and C. If each workstation is talking to one another and sending
broadcast traffic, the Layer-2 table on the SSR’s port would contain the following entries
for the workstations (assume that the VLAN ID is 1 for all entries):
Table 9. Bridging Modes
Port Configuration Entries
Flow-based bridging • MAC addresses A->B
• MAC addresses A->C
• MAC addresses B->A
• MAC addresses B->C
• MAC addresses C->A
• MAC addresses C->B
• MAC addresses A->broadcast
• MAC addresses B->broadcast
• MAC addresses C->broadcast
Address-based bridging • MAC address A
• MAC address B
• MAC address C
• MAC broadcast address