Transparent bridging
The intelligence necessary to make relaying decisions exists in the bridge itself and is thus
transparent to the communicating workstations. It involves frame forwarding, learning
workstation addresses, and ensuring no topology loops exist (in conjunction with the
Spanning-Tree algorithm).
UDP
User Datagram Protocol - A connectionless transport protocol that runs on top of TCP/IP's
IP. UDP, like TCP, uses IP for delivery; however, unlike TCP, UDP provides for exchange
of datagram without acknowledgments or guaranteed delivery. Best suited for small,
independent requests, such as requesting a MIB value from an SNMP agent, in which first
setting up a connection would take more time than sending the data.
UNI signaling
User Network Interface signaling for ATM communications.
Virtual Connection (VC)
A link that seems and behaves like a dedicated point-to-point line or a system that delivers
packets in sequence, as happens on an actual point-to-point network. In reality, the data is
delivered across a network via the most appropriate route. The sending and receiving
devices do not have to be aware of the options and the route is chosen only when a
message is sent. There is no pre-arrangement, so each virtual connection exists only for
the duration of that one transmission.
WAN
Wide area network - A data communications network that spans any distance and is usually
provided by a public carrier (such as a telephone company or service provider).
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