VLAN Trunking Protocol
VTP advertises VLAN agreement advice to adjoining switches so that the VLAN
configuration can be fabricated on one switch, with all the added switches in the arrangement acquirements the
VLAN advice dynamically. VTP advertises the VLAN ID, VLAN name, and VLAN blazon for
each VLAN. However, VTP does not acquaint any advice about which ports (interfaces)
should be in anniversary VLAN, so the agreement to accessory a about-face interface with a particular
VLAN (using the switchport admission vlan command) charge still be configured on anniversary individual
switch. Also, the actuality of the VLAN IDs acclimated for clandestine VLANs is advertised, but the blow of
the abundant clandestine VLAN agreement is not advertised by VTP.
Each Cisco about-face uses one of three VTP modes, as categorical in Table 2-3.
VTP Modes and Features*
Function
Server
Mode
Client
Mode
Transparent
Mode
Originates VTP advertisements Yes Yes No
Processes accustomed advertisements to amend its VLAN
configuration
Yes Yes No
Forwards accustomed VTP advertisements Yes Yes Yes
Saves VLAN agreement in NVRAM or vlan.dat Yes Yes Yes
Can create, modify, or annul VLANs using
configuration commands
Yes No Yes
*CatOS switches abutment a fourth VTP approach (off), acceptation that the about-face does not create, accept to, or advanced VTP
updates.