Information technology - Telecommunications and information exchange between systems - High-level data link control (HDLC) procedures - Classes of procedures
DATA ORGANIZATION, DATA PROCESSING, DATA TRANSMISSION CONTROL, COMMUNICATIONPROCEDURES, INFORMATION EXCHANGE, TELECOMMUNICATIONS, HIGH-LEVEL DATA LINKCONTROL, PROCEDURES, TELECOMMUNICATION TRANSMISSION METHODS
被代替标准
1999-01-01
适用范围
The international community has decided to make this standard available only in
the English language version. It has been adopted as a National Standard of
Canada on this basis. This National Standard of Canada is equivalent to International Standard
ISO/IEC 7809:1993. 1 Scope This International Standard describes the HDLC unbalanced classes of
procedures, the HDLC balanced class of procedures, and the HDLC connectionless
classes of procedures for synchronous or start/stop data transmission. Balanced operation is intended for use in circumstances which require equal
control at either end of the data link, Operational requirements are covered in
accordance with the overall HDLC architecture. The procedures use the HDLc
frame structure defined in ISO/IEC 3309 and the HDLC elements of procedures
described in ISO/IEC 4335. For the unbalanced classes, the data link consists of a primary station plus
one or more secondary stations and operates in either the normal response mode
or the asynchronous response mode in a point-to-point or multipoint
configuration For the balanced class, the data link consists of two combined
stations and operates in the asynchronous balanced mode in a point-to-point
configuration. For the unbalanced connectionless class, the data link consists
of a control station plus one or more tributary stations and operates in the
unbalanced connectionless-mode in a point-to point or multipoint configuration.
For the balanced connectionless class, the data link consists of two peer
stations and operates in the balanced connectionless-mode in a point-to-point
configuration. In each class, a basic repertoire of commands and responses is
defined but the capability of the data link may be modified by the use of
optional functions.