User`s guide

3-1
Chapter 3
Using ATX Trunking
The Trunking Table window; enabling and disabling trunking
Trunking, an extension of the 802.1D Spanning Tree protocol, allows you to
increaseaggregatebandwidth whentwo ormore switches areconnected.A single
10BASE-T connection between switches yields 10 or 100 Mbps of bandwidth,
depending on the speed of the ports used for the connection. A trunk group is
created when two or more ports on the same switch (for which trunking protocol
is enabled) are physically connected to the same remote switch. By creating a
trunk group, each additional connection results in another 10 or 100 Mbps of
bandwidth, since the group of ports effectively acts as a single connection. The
trunking protocol modifies Spanning Tree to allow the redundant links which
form a trunk group. Trunking can be enabled or disabled for a port using the
Trunking Table window (Figure 3-1). Trunking can be enabled for use on up to
eight ports per switch, allowing you to configure up to four trunk groups
potentially yielding 80 or 800 Mbps of bandwidth, depending on the speed of the
interfaces.
To display the Trunking Table window from the ATX Chassis View:
1. Click on the PPE’s Module Index (Module 1). The Module menu will appear.
2. Drag down Port Trunking, and release. The Port Trunking window,
Figure 3-1, will appear.
NOTE
Although youcan enabletrunking for more thaneight ports in your ATX chassis (ifmore
than eight ports exist in your chassis), the trunking protocol prohibits the use of trunking
on more than eight ports at a time. If you enable trunking and establish a valid link for a
ninth port,the extra port will bein “hot standby” mode. If connectionsare broken forany
of the original eight trunk ports, the hot standby port will then participate in trunking,
provided that it has a valid link to a remote switch which is participating in a trunk
group.