VTP - Versions

The Virtual Trunk Protocol (VTP) is a Cisco proprietary protocol used in network management. It helps manage the addition, deletion, and renaming of VLANs (Virtual Local Area Networks) on a network-wide basis. VTP helps maintain consistency throughout a network and simplifies the management of VLANs. There are three versions of VTP: VTP version 1, VTP version 2, and VTP version 3. Here's a brief overview of each:

1. VTP Version 1:

   • This is the original version of VTP.
   • It supports VLANs 1 to 1001.
   • It propagates VLAN information only if the VLANs are configured in the same VTP domain.
   • It does not recognize or propagate information about extended range VLANs (VLANs 1006-4094).
   • Lacks support for Token Ring VLANs or advanced features.

2. VTP Version 2:

   • An enhancement over Version 1.
   • Provides the same functions as VTP Version 1 but with added enhancements.
   • Adds support for Token Ring VLANs.
   • Includes consistency checks for certain operations, like renaming VLANs.
   • It has the capability to handle unknown TLV (Type-Length-Value) information.
   • Transparent mode switches can forward VTP advertisements in version 2.

3. VTP Version 3:

   • A significant improvement over the previous versions.
   • Supports extended range VLANs (VLANs 1006-4094).
   • Provides better control over which switches in the VTP domain can create VLANs.
   • Adds support for databases other than just the VLAN database. For example, it can manage MST (Multiple Spanning Tree) instances.
   • Includes features for enhanced security like protection against unintended database overrides and password protection.
   • Introduces primary and secondary VTP servers.
   • Allows for the propagation of private VLAN information.

Each subsequent version of VTP added more features and functionalities, improving VLAN management and network stability. However, it's important to note that VTP, being Cisco proprietary, works only on Cisco devices.