ZyXEL Communications Prestige 724, User Manual

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Prestige 724 G.SHDSL CSU/DSU
P Glossary
destination that ATM traffic will use. See also, VPI.
VPI
Virtual Path Identifier. AVPI is a number that denotes a bundle of virtual channels. A
VPI specifies the path and destination that ATM traffic will use. See also, VCI.
WAN
Wide Area Networks link geographically dispersed offices in other cities or around
the globe. Just about any long-distance communication medium can serve as a WAN
link including switched and permanent telephone circuits, terrestrial radio systems
and satellite systems.
WWW World Wide Web. Frequently used (incorrectly) when referring to "The Internet".
WWW has two major definitions. One, the whole constellation of resources that can
be accessed using Gopher, FTP, HTTP, telnet, USENET, WAIS and other tools.
Two, the universe of hypertext servers (HTTP servers).
X Series
Recommen-
dations
X.xx or X Series Recommendations are the international modem/telephone network
standards. The X.xx series recommendations are from the ITU-TS
(Telecommunication Standardization Sector of the International Telecommunications
Union) and will probably replace the old American Telephone and Telegraph
Company/Bell System MNP (Microcom Networking Protocol) standards. Some
modems offer both MNP and ITU-T standards; however, MNP generally offers much
lower transfer rates than the X.xx series. See also, X.21 Data Port Interface.
X.21 Data Port
Interface V.21 is a standard transfer rate implemented under recommendations by the ITU-TS
(Telecommunication Standardization Sector of the International Telecommunications
Union). X.21 provides the trunk interface between a network access device and a
packet network. X.21 may use the bandwidths of several telephone circuits as a
group. See also, X Series Recommendations.
xDSL
Digital Subscriber Line(s) where x, when specified, denotes a particular flavor of
DSL, eg., ADSL, G.SHDSL, SDSL, VDSL, RDSL, etc.
ZyNOS ZyXEL Network Operating System is the firmware used in many ZyXEL products.