Olicom CrossFire 8730, Reference Manual

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CrossFire 8730 Switch Reference Guide, DOC-7047 v. 1.1 Switch Overview
Address Management
At power up, the system address tables do not contain any information. Whenever
a switch receives a packet with an unknown source or destination address, it learns
the new source address and stores its location in coming port in the address table.
If the destination address is unknown it sends the packet to all ports that can receive
data from the incoming port. When the response packet comes back, the switch will
learn the responder’s location and adds it to the address table. Once the address
table entries are created, the switch uses these learned address to switch all
subsequent packets to the port where the destination address is located.
The system address table maintains up to 10,000 entries. Each Token-Ring port
address table maintains 5,500 active addresses (each port address table is shared by
four ports, as follows: 1-4, 5-8, 9-12, 13-, etc.). If an address has not been active for
a configurable aging time, it is removed from the table. Each Fast Ethernet port
maintains up to 15,000 active addresses. Unlike Token-Ring ports, that need local
and transparent addresses only, a Fast Ethernet port must know all the active
addresses in the network.
Multiple Bridging Modes
The CrossFire 8730 supports four different switching modes to provide maximum
flexibility in all installation environments. The switching modes are Source Route
Switching (SRS), Source Route Bridging (SRB), Source Route Transparent (SRT)
and SRT/SRB. The switch operates on two levels (BRF and CRF) as outlined below.
Figure 5. Typical Configuration with Switches Using Multiple Bridging Modes
BRF 1
CRF 1 CRF 2
CRF 3 CRF 4
Switch