ISLCisco's proprietary method of trunk encapsulation for carrying VLANs over FE and GE. You use the VLAN header and trailer outside the frame (external tag).
IEEE 802.1qIEEE standard for trunk encapsulation for carrying VLANs over FE and GE. Uses internal 4-byte tag that is placed before the Type/Length field of frames.
VTPCisco's method of distributing VLAN information between Catalyst switches.
VLAN pruningLimits the flooding of broadcasts to switches that do not require them.