C-8
Glossary
Pair").
UTP (Unshielded Twisted-Pair)
See "Twisted-Pair" and "Shielded Twisted-Pair".
Virtual LAN (VLAN)
A portion of one or more LAN switches which delivers packets as if it were a
physical LAN; actually like a switched LAN. The most primitive VLAN
facility that a switch can have allows the switch to be partitioned into two or
more groups of ports (VLANs) within which communication is possible, but
between which communication is blocked. More complex is a feature which
allows each VLAN to reside on two or more switches (e.g. some of VLAN
A's ports are on switch 1 and some of its ports are on switch 2; and the same
for VLAN B) even though the two switches are connected through a single
physical interface. The most complex is provision for VLANs that overlap,
i.e. port 1 of a switch is on VLAN A and VLAN B, while port 2 is on VLAN
A but not VLAN B, etc. The term "Virtual Network" is also used.
WAN "Wide Area Network"
A term for state/country/world-wide networks developed to parallel the term
LAN for "Local Area Network".