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Communications Programming Concepts AIX Version 7.1 Communications Programming Concepts IBM Note Before using this information and the product it supports, read the information in “Notices” on page 323 . This edition applies to AIX Version 7.1 and to all subsequent releases and modifications until otherwise indicated in new editions. © Copyright International Business Machines Corporation 2010, 2014. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents About this document............................................................................................vii How to use this document..........................................................................................................................vii Highlighting.................................................................................................................................................vii Case-sensitivity in AIX................................................................................................................................vii ISO 9000.....................................................................................................................................................vii Communication Programming Concepts................................................................. 1 Data Link Control..........................................................................................................................................1 Generic Data Link Control Environment Overview................................................................................ 1 Implementing GDLC Interface............................................................................................................... 3 GDLC Interface ioctl Entry Point Operations......................................................................................... 4 GDLC Special Kernel Services................................................................................................................ 7 GDLC Problem Determination................................................................................................................ 7 Data Link Control Programming and Reference Information..............................................................10 Token-Ring Data Link Control Overview.............................................................................................. 12 DLCTOKEN Device Manager Nodes......................................................................................................13 DLCTOKEN Device Manager Functions................................................................................................ 14 DLCTOKEN Protocol Support............................................................................................................... 15 DLCTOKEN Name-Discovery Service...................................................................................................17 DLCTOKEN Direct Network Services....................................................................................................20 DLCTOKEN Connection Contention..................................................................................................... 21 Initiating DLCTOKEN Link Sessions..................................................................................................... 21 Stopping DLCTOKEN Link Sessions..................................................................................................... 22 DLCTOKEN Programming Interfaces................................................................................................... 22 IEEE 802.3 Ethernet Data Link Control Overview............................................................................... 27 DLC8023 Device Manager Nodes.........................................................................................................27 DLC8023 Device Manager Functions...................................................................................................28 DLC8023 Protocol Support.................................................................................................................. 29 DLC8023 Name-Discovery Services.................................................................................................... 30 DLC8023 Direct Network Services.......................................................................................................34 DLC8023 Connection Contention........................................................................................................ 34 DLC8023 Link Sessions........................................................................................................................34 DLC8023 Programming Interfaces...................................................................................................... 36 Standard Ethernet Data Link Control Overview...................................................................................39 DLCETHER Device Manager Nodes...................................................................................................... 40 DLCETHER Device Manager Functions................................................................................................ 41 DLCETHER Protocol Support................................................................................................................42 DLCETHER Name-Discovery Services..................................................................................................43 DLCETHER Direct Network Services.................................................................................................... 47 DLCETHER Connection Contention......................................................................................................47 DLCETHER Link Session Initiation....................................................................................................... 47 DLCETHER Link Session Termination...................................................................................................48 DLCETHER Programming Interfaces....................................................................................................49 Synchronous Data Link Control Overview............................................................................................52 DLCSDLC Device Manager Functions................................................................................................... 53 DLCSDLC Protocol Support.................................................................................................................. 53 DLCSDLC Programming Interfaces...................................................................................................... 56 DLCSDLC Asynchronous Function Subroutine Calls............................................................................61 Qualified Logical Link Control (DLCQLLC) Overview............................................................................ 61 Data Link Control FDDI (DLC FDDI) Overview..................................................................................... 67 iii DLC FDDI Device Manager Nodes........................................................................................................ 68 DLC FDDI Device Manager Functions.................................................................................................. 69 DLC FDDI Protocol Support..................................................................................................................70 DLC FDDI Name-Discovery Services....................................................................................................71 DLC FDDI Direct Network Services...................................................................................................... 75 DLC FDDI Connection Contention........................................................................................................75 DLC FDDI Link Sessions....................................................................................................................... 76 DLC FDDI Programming Interfaces......................................................................................................77 Data Link Provider Interface Implementation.......................................................................................... 81 Primitive Implementation Specifics.................................................................................................... 82 Packet Format Registration Specifics.................................................................................................. 82 Address Resolution Routine Registration Specifics............................................................................ 83 ioctl Specifics........................................................................................................................................84 Dynamic Route Discovery.................................................................................................................... 86 DRD Configuration................................................................................................................................ 87 Connectionless Mode Only DLPI Driver versus Connectionless/Connection-Oriented DLPI Driver............................................................................................................................................... 87 Obtaining Copies of the DLPI Specifications......................................................................................
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