HP 600 Series, Услуги и приложения

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The first formal Frame Relay specification was developed by the Frame
Relay Forum (FRF), a group of companies that included Digital Equipment
Corp., Cisco, Northern Telecom, and StrataCom. This specification, released
in September, 1990, was based upon existing standards and ongoing work in
the ANSI T1S1 committees. The FRF enhanced the basic data-transfer-proto-
col procedures defined in the ANSI standards, by adding the Local Manage-
ment Interface (LMI) and some optional functions (which are discussed
later).
In 1991, ANSI released T1.617, “ISDN—Signaling Specification for Frame
Relay Bearer Service”, and T1.618, “ISDN—Core Aspects of Frame Protocol
for use with Frame Relay Bearer Service”. In 1992, CCITT released Recom-
mendation Q.922, “ISDN Data Link Layer Specification for Frame Mode
Bearer Services”, and Draft Recommendation Q.933, “Digital Subscriber
Signaling System No. 1 (DSS 1), Signaling Specification for Frame Mode
Basic Call Control”.
Frame Relay services were first introduced in March, 1991, in the U.S. by
WilTel, an interexchange carrier. Frame Relay announcements soon followed
by other U.S. interexchange and local exchange carriers as well as the
international exchange carriers.
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Linking Up with Frame Relay
History
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