Cisco 10008 Hardware Installation Manual page 164

Glossary
U
See
Unchannelized DS3
A message sent to a single network destination. Compare with
Unicast
V
See VPN.
Virtual Private
Network
Virtual LAN. A group of devices on one or more LANs that are configured (using management
VLAN
software) so that they can communicate as if they were attached to the same wire, when in fact they are
located on a number of different LAN segments. Because VLANs are based on logical instead of
physical connections, they are extremely flexible.
Voice over IP. Voice over IP enables a router to carry voice traffic (for example, telephone calls and
VoIP
faxes) over an IP network.
Virtual private network. A secure, end-to-end private network constructed over a third-party or public
VPN
network such as the Internet.
Virtual tributary level n. The SONET format for mapping a lower-rate signal into a SONET payload.
VT-n
For example, VT-1.5 is used to transport a DS1 signal. See also
W
Wide-area network. A data communications network that serves users across a broad geographic area
WAN
and often uses transmission devices provided by a common carrier (such as a telephone company or
service provider).
See WFQ.
Weighted Fair
Queuing
See WRED.
Weighted Random
Early Detection
Weighted Fair Queuing. Congestion management algorithm that identifies conversations (in the form
WFQ
of traffic streams), separates packets that belong to each conversation, and ensures that capacity is
shared fairly between these individual conversations. WFQ is an automatic way of stabilizing network
behavior during congestion and results in better performance and fewer retransmissions.
Cisco 10008 Router Hardware Installation Guide
GL-14
Clear channel DS3.
Broadcast and Multicast.
DS1 and SONET.
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