资料来源 : Free On-Line Dictionary of Computing

Frame Relay
     
         A {DTE}-{DCE} interface specification based
        on {LAPD} (Q.921), the {Integrated Services Digital Network}
        version of {LAPB} ({X.25} {data link layer}).  A common
        specification was produced by a consortium of {StrataCom},
        {Cisco}, {Digital}, and Northern Telecom.
     
        Frame Relay is the result of {wide area network}ing
        requirements for speed; {LAN}-{WAN} and LAN-LAN
        {internetworking}; "bursty" data communications; multiplicity
        of {protocol}s and {protocol transparency}.  These
        requirements can be met with technology such as {optical
        fibre} lines, allowing higher speeds and fewer transmission
        errors; intelligent network end devices ({personal computers},
        {workstations}, and {servers}); standardisation and adoption
        of ISDN protocols.  Frame Relay could connect dedicated lines
        and {X.25} to {ATM}, {SMDS}, {BISDN} and other "{fast packet}"
        technologies.
     
        Frame Relay uses the same basic {data link layer} {framing} and
        {Frame Check Sequence} so current {X.25} hardware still works.
        It adds addressing (a 10-bit {Data Link Connection Identifier}
        (DLCI)) and a few control bits but does not include
        retransmissions, link establishment, windows or error
        recovery.  It has none of X.25's {session layer} but adds some
        simple interface management.  Any {network layer} protocol can
        be used over the data link layer Frames.
     
        {Frame Relay Resource Center
        (http://www.alliancedatacom.com/framerelay.asp)}.
     
        (2000-07-14)