3Com 3500 manual Trunks

11

TRUNKS

You can configure a system to aggregate multiple network links into a single trunk. With trunking you can create high-speed point-to-point or multipoint connections without changing or replacing existing cabling. In addition, trunking provides automatic point-to-point redundancy between two devices. Redundant links normally have one link disabled by Spanning Tree (to prevent looping); trunking utilizes both links.

This chapter provides guidelines and other key information about how to configure trunking in your system.

The system treats trunked bridge ports in the same way that it treats normal individual bridge ports. Also, all higher-level network functions — including Spanning Tree algorithms, virtual LANs (VLANs), and Simple Network Management Protocol (SNMP) management — do not distinguish a trunk from any other network port. Unlike for any other network port, the system automatically distributes traffic across the ports that are associated with a trunk. If any of the trunk’s ports go down or up, the system automatically redistributes traffic across the new arrangement of operational ports.

For more trunking information, see the Implementation Guide for your system.

Trunks can work with MultiPoint Link Aggregation (MPLA). MPLA is a feature for the CoreBuilder® 9400 that increases the capacity and availability of campus LAN cores without using complex, meshed router networks. Functioning at Layer 2, MPLA provides both dual-homed link resiliency and automatic load sharing over point-to-multipoint backbone connections. MPLA increases network availability using scalable Gigabit Ethernet connections among multiple campus switches. For more information about MPLA and trunking, see the CoreBuilder 9400 Implementation Guide.