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/* $OpenBSD: README.hdlc,v 1.3 2003/01/04 22:36:12 deraadt Exp $ */
/* $NetBSD: README.hdlc,v 1.4 1994/06/29 06:36:58 cgd Exp $ */
/*
* Copyright (c) University of British Columbia, 1984
*
* @(#)README.hdlc 8.1 (Berkeley) 6/10/93
*
* X.25 HDLC DATA LINK LEVEL:
*
*
* This module implements the Link Level of the Open Systems Interconnect
* Model. The implementation is based on the ISO High-Level Data Link
* Control (HDLC). These procedures subscribe to the principles of the
* ISO-Class of Procedures for point-to-point. These procedures implement
* two-way asynchronous balanced mode (LAPB) as recommented by the CCITT.
*
* The HDLC protocol layer interface consists of the following procedures:
* Hd_init (pr_init)
* Hd_output (pr_output)
* Hd_input (pr_input)
* Hd_timer (pr_slowtimo)
*
* Note: Supervisory commands RR, RNR and REJ are not transmitted by this
* station.
*
* This station never enters a busy (RNR) condition.
*
* The "Generate_rr" variable can be set to FALSE. This means that
* we NEVER send an RR. This works just fine if the network level
* is X.25 packet protocol -- which it is.
*
* Currently, this is only a DTE implementation.
*
* Think about:
* If the remote is busy, no iframes are sent. The remote sends a RR
* to clear this condition. However, this RR may be damaged, causing
* a possible deadlock. A solution is to poll with iframe (P(S)==P(R)
* of RNR) indefinitly.
*
*
* Date: February 1984
*
* Author: Gerald W. Neufeld
*
* Installation: Department of Computer Science
* University of British Columbia
* Vancouver, BC, CANADA.
*
* History:
*
*
*/
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