Cabletron Systems STS16-20R manual Address Management, SmartStack STS16-20D Token Ring Switch

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Address Management

At power up, the system address tables do not contain any information. Whenever

aSmartStack STS16-20D/STS16-20R 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 SmartStack STS16-20D/STS16-20R will learn the responder’s location and adds it to the address table. Once the address table entries are created, the SmartStack STS16-20D/STS16-20R uses these learned address to switch all subsequent packets to the port where the destination address is located.

SmartStack STS16-20D Token Ring Switch

The system address table maintains up to 10,000 entries known across the networks and stations attached to the switch.

On SmartStack STS16-20D, the local port address table for the designated network ports 17 to 20 maintains up to 5,500 active Token Ring addresses. If more than this maximum number of addresses appear as a source MAC address, these additional addresses will not be learned, resulting in frames from these additional addresses being sent to all switch ports.

The workstation ports 1 to 16 maintain one active Token Ring address per port. If more than one address appears as a source MAC address, these additional addresses will not be learned, and frames from these additional addresses will be not be forwarded.

Addresses on both workstation and network ports are monitored for activity. If an address has not been active for a configurable aging time, the address is removed from the address tables. This ensures that the port’s address table is populated only by the most recently used addresses.

This capability allows users to transparently connect to high-volume backbone networks.

SmartStack STS16-20R Token Ring Switch

The system address table maintains up to 10,000 entries. On SmartStack STS16- 20R each port address table maintains 5,500 active Token Ring addresses (each port address table is shared by four ports, using the following: 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 tables. This ensures that the port’s address table is populated only by the most recently used address.

Just as on SmartStack STS16-20D, this capability allows users to transparently connect to high-volume backbone networks.

SmartStack STS16-20D/STS16-20R Token Ring Switches Installation and User Guide Switch Overview