mskuhn@faui09.informatik.uni-erlangen.de (Markus Kuhn) (04/02/91)
Here comes some information for everybody interested in
ISO HDLC (the base standard of LAP-B, LAP-M, LAP-D, PPP, ...).
HDLC is a OSI data link layer standard for synchronous and
asynchronous (= start/stop) transmission.
The following list of standards has been copied from
Computer Communication Review, Jan 1991.
ISO DIS 3309 HDLC - Frame Structure
ISO 3309/Add.1 Addendum 1: Start/Stop Transmission
ISO 3309/DAM2 Amendment 2: Extended Transparency Options
for Start/Stop Transmission
ISO 3309/PDAM3 Amendment 3: Seven-bit Transparency Option
for Start/Stop Transmission
ISO DIS 4335 HDLC - Consolidation of Elements of Procedures
ISO 4335/Add.1 Addendum 1: (no title; contains UI and SREJ
extensions)
ISO 4335/Add.2 Addendum 2: Enhancement of the XID Function
Utility
ISO 4335/Add.3 Addendum 3: Start/Stop Transmission
ISO 4335/DAM4 Amendment 4: Multi-Selective Reject Option
ISO DIS 7809 HDLC - Consolidation of Classes of Procedures
ISO 7809/Add.1 Addendum 1: (no title; contains UI extensions)
ISO 7809/Add.2 Addendum 2: Description of Optional Functions
ISO 7809/Add.3 Addendum 3: Start/Stop Transmission
ISO 7809/DAM5 Amendment 5: Connectionless Class of Procedures
ISO 7809/DAM6 Amendment 6: Extended Transparency options
for Start/Stop Transmission
ISO 7809/DAM7 Amendment 7: Multi-Selective Reject Option
ISO 7809/DAM9 Amendment 9: Seven-bit Transparency Options
for Start/Stop Transmission
ISO 8885 HDLC - General Purpose XID Frame Information
Field Content and Format
ISO 8885/Add.1 Addendum 1: Additional Operational Parameters
for the Parameter Negotiation Data
Link Layer Subfield and Definition
of a Multilink Parameter Negogiation
Data Link Layer Subfield
ISO 8885/Add.2 Addendum 2: Start/Stop transmission
ISO 8885/DAM3 Amendment 3: Definition of a Private Parameter
Negotiation Data Link Layer Subfield
ISO 8885/DAM4 Amendment 4: Extended Transparency Options
for Start/Stop Transmission
ISO 8885/DAM5 Amendment 5: Multi-Selective Reject Option
ISO 8885/PDAM6 Amendment 6: Seven-bit Transparency Option for
Start/Stop Transmission
ISO 8885/PDAM7 Amendment 7: Frame Check Sequence Negotiation
Using the Parameter Negotiation
Subfield
ISO TR 10171 List of Standard Data Link Layer Protocols
that Utilise High-Level Data Link Control (HDLC)
Classes of Procedures
ISO 10171/PDAM1 Ammendment 1: Registration of XID Format
Identifiers and Private Parameter
Set Identifiers
--
Markus Kuhn, Computer Science student
University of Erlangen, Germanymskuhn@faui09.informatik.uni-erlangen.de (Markus Kuhn) (04/02/91)
Has anybody information about the following two extentions to HDLC: - Extended Transparency Options for Start/Stop Transmission - Seven-bit Transparency Option for Start/Stop Transmission I'd be quite interested in this, because I plan to implement asynch HDLC on a PC. Are there any standards (V.42ter, X.32bis, ???) in development that use Start/Stop HDLC? Are there any modems that use Start/Stop HDLC and convert it in normal HDLC? Thank you for any help. -- Markus Kuhn, Computer Science student University of Erlangen, Germany
tnixon@hayes.uucp (04/03/91)
In article <mskuhn.670600487@faui09>, mskuhn@faui09.informatik.uni-erlangen.de (Markus Kuhn) writes: > Has anybody information about the following two extentions > to HDLC: > > - Extended Transparency Options for Start/Stop Transmission > - Seven-bit Transparency Option for Start/Stop Transmission You should be able to get these PDAMs through your country's ISO national body (DIN). The original work on these proposals was done here at Hayes back in 1985, and I presented them in the standards bodies initially back in 1986. ANSI X3S3.4 decided to push first for the standardization of the basic Start/Stop HDLC (AD 1) rather than try to explain the whole package to ISO/IEC JTC 1/SC 6/WG 1 all at once. I haven't been attending meetings of either of these committees for a couple of years, but apparently the current members of X3S3.4 have followed through and submitted the additional portions of the original Start/Stop HDLC proposal to ISO for consideration. > Are there any standards (V.42ter, X.32bis, ???) in development > that use Start/Stop HDLC? CCITT Study Group VII has initiated work on adding the Start/Stop HDLC framing mode to X.25 and X.32. I do not know the current status of that work, except that I know it's not done yet. A lot of PTTs and PSPDNs are very interested in it because of the potential market for value-added services to async-only PCs (without the need to add an HDLC card and synchronous modem). > Are there any modems that use Start/Stop HDLC and convert it in > normal HDLC? I am not aware of any. Hayes V-series modems support Start/Stop HDLC in two ways: Start/Stop LAPB protocol to retrofit error control features on older, async-only modems like the Smartmodem 1200; and, Start/Stop X.25 (which is pretty useless right now, since no network supports it yet!). But they don't provide direct pass-through conversion from Start/Stop HDLC to sync HDLC. Our modems DO provide the "Hayes AutoSync" feature, which permits conversion in the modem between async and sync data streams, but the async data format is not according to 3309/AD 1 (it is simpler; no transparency required, and the FCS calculation is done in the modem). -- Toby -- Toby Nixon, Principal Engineer | Voice +1-404-840-9200 Telex 151243420 Hayes Microcomputer Products Inc. | Fax +1-404-447-0178 CIS 70271,404 P.O. Box 105203 | UUCP uunet!hayes!tnixon AT&T !tnixon Atlanta, Georgia 30348 USA | Internet hayes!tnixon@uunet.uu.net
jh@funet.fi (Juha Heinanen) (04/04/91)
While we are at HDLC, does anyone know when US GOSIP is going to define a reasonable variant of HDLC to be used to run CLNP over point-to-point links? The current spec is very vague on this and seems to mention CLNP over LAP-B. If I remember correctly, LAP-B is a window based version of HDLC that doesn't support high-speed, long delay media. Also, running multiple protocols, some of which are non-OSI, is not possible using the current specification. -- -- Juha Heinanen, FUNET, Finland, jh@funet.fi, +358 49 500958
sklower@okeeffe.Berkeley.EDU (Keith Sklower) (04/04/91)
In article <JH.91Apr3185415@etana.funet.fi> jh@funet.fi (Juha Heinanen) writes: }While we are at HDLC, does anyone know when US GOSIP is going to }define a reasonable variant of HDLC to be used to run CLNP over }point-to-point links? ... running multiple protocols, some of which are }non-OSI, is not possible using the current specification. }-- Juha Heinanen, FUNET, Finland, jh@funet.fi, +358 49 500958 I think you should examine the internet PPP spec. It uses HDLC framing, but with different ``addresses'', and could be compatible with standard LAP_B for an implementation that understood both. There are hooks left for running CLNP and XNS traffic, although only the IP details are completely nailed down. Keith Sklower Computer Science Dept. sklower@okeeffe.Berkeley.EDU 570 Evans Hall (415) 642-9587 University of California H: (415) 863-0990 Berkeley, CA 94720