Lucent Technologies Release 8.2 Manual Do Utilizador

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virtual circuit (virtual connection) 
489
Administration for Network Connectivity
555-233-504 — Issue 1 — April 2000
CID: 77730
  
Glossary
virtual circuit (virtual connection)
The pre-arranged route through the 
 network that all cells in an ATM 
transmission follow.
virtual circuit number
The route identifier contained in an 
 cell header. A 
 and 
 together 
constitute the virtual circuit number.
virtual path identifier
.
VPI
 virtual path identifier. ATM is a connection-oriented service that sets 
up a virtual circuit between the transmitter and the receiver. The two endpoints 
negotiate an agreed route through the network before sending any data. VCI 
and VPI together constitute the virtual circuit number that identifies this route. 
The VPI is analogous in some ways to an 
 trunk group. 
W
WAN
.
well-known address
The default network address for a given type of network component, as 
specified by a communications protocol or standards body. For example, the 
ATM Forum defines well-known addresses for LAN-emulation servers and 
LAN-emulation configuration servers. 
well-known port
port numbers that are assigned to specific applications by IANA. For example, 
21 for FTP, 23 for Telnet, 110 for pop3.
wide area network
A data network that connects 
 (LANs) using 
common-carrier telephone lines, 
, and 
wideband
A circuit-switched call at a data rate greater than 64 kbps. A circuit-switched 
call on a single T1 or E1 facility with a bandwidth between 128 and 1536 (T1) 
or 1984 (E1) kbps in multiples of 64 kbps. H0, H11, H12, and N x DS0 calls are 
wideband.