【資料名稱】：ISDN USER-NETWORK INTERFACE-DATA

【資料作者】：ITU-T

【資料日期】：2000

【資料語言】：英文

【資料格式】：DOC

【資料目錄和簡介】：

CONTENTS
Recommendation Q.921 (03/93)
Page
1General ...........................................................................................................................................................1
2Frame structure for peer-to-peer communication ...........................................................................................1
2.1General..............................................................................................................................................1
2.2Flag sequence....................................................................................................................................1
2.3Address field .....................................................................................................................................1
2.4Control field......................................................................................................................................2
2.5Information field ...............................................................................................................................2
2.6Transparency.....................................................................................................................................3
2.7Frame check sequence (FCS) field ...................................................................................................3
2.8Format convention ............................................................................................................................3
2.9Invalid frames ...................................................................................................................................5
2.10Frame abort .......................................................................................................................................5
3Elements of procedures and formats of fields for data link layer peer-to-peer communication .....................5
3.1General..............................................................................................................................................5
3.2Address field format .........................................................................................................................5
3.3Address field variables......................................................................................................................5
3.4Control field formats.........................................................................................................................7
3.5Control field parameters and associated state variables....................................................................8
3.6Frame types.......................................................................................................................................10
4Elements for layer-to-layer communication ...................................................................................................13
4.1General..............................................................................................................................................13
4.2Primitive procedures .........................................................................................................................18
4.3Block interaction diagram of the data link layer ...............................................................................18
5Definition of the peer-to-peer procedures of the data link layer.....................................................................22
5.1Procedure for the use of the P/F bit...................................................................................................22
5.2Procedures for unacknowledged information transfer ......................................................................22
5.3Terminal endpoint identifier (TEI) management procedures............................................................23
5.4Initialization of data link layer parameters........................................................................................32
5.5Procedures for establishment and release of multiple frame operation.............................................33
5.6Procedures for information transfer in multiple frame operation......................................................36
5.7Re-establishment of multiple frame operation ..................................................................................40
5.8Exception condition reporting and recovery .....................................................................................41
5.9List of system parameters .................................................................................................................43
5.10Data link layer monitor function.......................................................................................................44