Chapter 8      Configuring VLANs
Using VTP
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Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide
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VTP advertisements distribute the following VLAN information for each 
configured VLAN:
• VLAN ID
• VLAN name
• VLAN type
• VLAN state
• Additional VLAN configuration information specific to the VLAN type
VTP Version 2
VTP version 2 supports the following features not supported in version 1:
• Token Ring support—VTP version 2 supports Token Ring LAN switching 
and VLANs (Token Ring Bridge Relay Function [TrBRF] and Token Ring 
Concentrator Relay Function [TrCRF]). For more information about Token 
Ring VLANs, see the “VLANs in the VTP Database” section on page 8-27.
• Unrecognized Type-Length-Value (TLV) support—A VTP server or client 
propagates configuration changes to its other trunks, even for TLVs it is not 
able to parse. The unrecognized TLV is saved in nonvolatile RAM when the 
switch is operating in VTP server mode.
• Version-Dependent Transparent Mode—In VTP version 1, a VTP transparent 
switch inspects VTP messages for the domain name and version and forwards 
a message only if the version and domain name match. Because only one 
domain is supported, VTP version 2 forwards VTP messages in transparent 
mode without checking the version and domain name.
• Consistency Checks—In VTP version 2, VLAN consistency checks (such as 
VLAN names and values) are performed only when you enter new 
information through the CLI, the Cluster Management software, or SNMP. 
Consistency checks are not performed when new information is obtained 
from a VTP message or when information is read from nonvolatile RAM. If 
the digest on a received VTP message is correct, its information is accepted 
without consistency checks.