3Com LANplex 6000 manual Trsm Description

2TRSM Description

TRSM Description The Token Ring Switching Module (TRSM) is designed to add Token Ring (TR) switching functionality to the LANplex 6000, providing the most cost effective solution for introducing segmentation for today's Token Ring networks, while allowing you to prepare for future higher bandwidth requirements such as multimedia applications.

The TRSM has eight shielded RJ-45 token ring ports on the front of the module and one FDDI backplane attachment which may be connected to any of the three LANplex chassis FDDI backplanes. All eight token ring switch ports support a full ring of 260 stations, with two of the ports able to accommodate direct station attachment for dedicated bandwidth to file servers and other critical resources. The shielded RJ-45 ports allow for attachment via Type 1 STP or Type 3, 4, or 5 UTP copper cable. Each port is independently configurable to support either 4 Mbps or 16 Mbps operation.

TRSM Configurable The TRSM is architected to support both source routed or transparent Bridge Modes traffic types in the following modes:

■Transparent (T)

■Source Routing (SR)

■Source Routing-Transparent Bridge (SRT) Transparent

The TRSM fully complies with the IEEE 802.1d bridging standard, which means that the module:

■Learns source addresses from packets transmitted by stations on LANs attached to TRSM ports

■Ages addresses of stations on attached LANs that have not transmitted a packet for a prolonged time

■Stores and forwards packets from one attached LAN to another

■Uses the Spanning Tree protocol for loop detection

The TRSM automatically “learns” the MAC-layer addresses of the stations on its attached networks, and then forwards packets to their appropriate destinations. Packet forwarding is based on learned or statically configured MAC addresses. The TRSM can learn up to 8192K addresses. Additional addresses are learned as addresses are aged out. All addresses are stored in