Understanding How Vlan Trunks Work; Trunking Overview - Cisco WS-C6506 Software Manual

Configuring Ethernet VLAN Trunks
This chapter describes how to configure Ethernet VLAN trunks on the Catalyst 6500 series switches.
For complete information on configuring VLANs, see
Note
Note For complete syntax and usage information for the commands that are used in this chapter, refer to the
Catalyst 6500 Series Switch Command Reference publication.
This chapter consists of these sections:
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Understanding How VLAN Trunks Work

These sections describe how VLAN trunks work on the Catalyst 6500 series switches:
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Trunking Overview

A trunk is a point-to-point link between one or more Ethernet switch ports and another networking
device such as a router or a switch. Trunks carry the traffic of multiple VLANs over a single link and
allow you to extend VLANs across an entire network.
Two trunking encapsulations are available on all Ethernet ports:
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OL-8978-04
Understanding How VLAN Trunks Work, page 5-1
Default Trunk Configuration, page 5-5
Configuring a Trunk Link, page 5-5
Example VLAN Trunk Configurations, page 5-14
Trunking Overview, page 5-1
Trunking Modes and Encapsulation Type, page 5-2
802.1Q Trunk Configuration Guidelines and Restrictions, page 5-4
Inter-Switch Link (ISL)—ISL is a Cisco-proprietary trunking encapsulation
IEEE 802.1Q—802.1Q is an industry-standard trunking encapsulation
C H A P T E R
Chapter 11, "Configuring VLANs."
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
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