VTP Advertisements

VTP Advertisements
After the different types of VTP switches are defined, the switches can start advertising VTP
information between them. VTP switches advertise information they know about only on their
trunk ports. They advertise the following:
 Management domain name
 Configuration revision number
 VLANs the switch knows about
 Parameters for each VLAN
The switches use multicast MAC addresses, so all neighbor devices receive the frames. A VTP
server creates new VLANs, and that information is propagated through the VTP domain.
Figure 14.5 shows the three VTP advertisements: client, summary, and subset.
The three types of messages are as follows:
Client requests Clients can send requests for VLAN information to a server. Servers respond
with both summary and subset advertisements.
Summary These advertisements are sent out every 300 seconds on VLAN 1 and every time a
change occurs.
Subset These advertisements are VLAN-specific and contain details about each VLAN.