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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
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Chapter 13 Configuring VLANs
Configuring VLAN Trunks
Configuring VLAN Trunks
These sections contain this conceptual information:
•
•
Encapsulation Types, page 13-17
•
Default Layer 2 Ethernet Interface VLAN Configuration, page 13-18
•
Configuring an Ethernet Interface as a Trunk Port, page 13-18
•
Configuring Trunk Ports for Load Sharing, page 13-23
Trunking Overview
A trunk is a point-to-point link between one or more Ethernet switch interfaces and another networking device
such as a router or a switch. Ethernet trunks carry the traffic of multiple VLANs over a single link, and you
can extend the VLANs across an entire network.
Two trunking encapsulations are available on all Ethernet interfaces:
•
Inter-Switch Link (ISL)—Cisco-proprietary trunking encapsulation.
•
IEEE 802.1Q— industry-standard trunking encapsulation.
shows a network of switches that are connected by ISL trunks.
Figure 13-2
Switches in an ISL Trunking Environment
shows a network of switches that are connected by IEEE 802.1Q trunks.
Catalyst 6500 series
switch
Blade
switch
Blade
switch
Blade
switch
Blade
switch
VLAN2
VLAN3
VLAN1
VLAN1
VLAN2
VLAN3
ISL
trunk
ISL
trunk
ISL
trunk
ISL
trunk
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