CHAPTER
14-1
Catalyst 6500 Series Switch Cisco IOS Software Configuration Guide—Release 12.1 E
78-14099-04
14
Configuring IEEE 802.1Q Tunneling and Layer 2
Protocol Tunneling
With Release 12.1(13)E and later, the Catalyst 6500 series switches support IEEE 802.1Q tunneling and
Layer 2 protocol tunneling. This chapter describes how to configure IEEE 802.1Q tunneling and Layer
2 protocol tunneling on the Catalyst 6500 series switches.
Note • For complete syntax and usage information for the commands used in this chapter, refer to the
Catalyst 6500 Series Switch Cisco IOS Command Reference publication.
• The WS-X6548-GE-TX, WS-X6548V-GE-TX, WS-X6148-GE-TX, and WS-X6148V-GE-TX
switching modules do not support IEEE 802.1Q tunneling or Layer 2 protocol tunneling.
This chapter consists of these sections:
• Understanding How 802.1Q Tunneling Works, page 14-1
• 802.1Q Tunneling Configuration Guidelines and Restrictions, page 14-4
• Configuring 802.1Q Tunneling, page 14-5
• Understanding How Layer 2 Protocol Tunneling Works, page 14-7
• Configuring Support for Layer 2 Protocol Tunneling, page 14-8
Understanding How 802.1Q Tunneling Works
802.1Q tunneling enables service providers to use a single VLAN to support customers who have
multiple VLANs, while preserving customer VLAN IDs and keeping traffic in different customer
VLANs segregated.
A port configured to support 802.1Q tunneling is called a tunnel port. When you configure tunneling,
you assign a tunnel port to a VLAN that you dedicate to tunneling, which then becomes a tunnel VLAN.
To keep customer traffic segregated, each customer requires a separate tunnel VLAN, but that one tunnel
VLAN supports all of the customer’s VLANs.
802.1Q tunneling is not restricted to point-to-point tunnel configurations. Any tunnel port in a tunnel
VLAN is a tunnel entry and exit point. An 802.1Q tunnel can have as many tunnel ports as are needed
to connect customer switches.
