Extended VLAN:
- Historically, Cisco Catalyst switches have supported
only up to 1024 VLANs
- ISL uses 10-bit VLAN ID which supports up to 1024 VLAN
- 802.1Q includes a 12-bit VLAN ID which supports upto
4096 VLAN
- Cisco refers to the VLANs between 1025 to 4096 as
extended-range VLANs
Cisco catalyst switches support extended-range VLANs
under the following restrictions,
VTP cannot be used for VLAN management
VTP must be configured in transparent mode or off
Only Ethernet VLANs are supported