The SNA Formats Manual (available mail order from IBM) is the best place to
start. If you are working on a product to support native LU2 and LU6.2,
with TN3270 style terminal service, you also will need the 3270 datastream
programmers manual since you will need to know how to deal with WSF (write
structured fields). Some of them, particularly those that suppoer 1472
style terminal commands (CSCM, EVPD, RTM) need to be intercepted and the
information returned correctly from linux stats. You will also need to
complete the work on the LLC 8022 stack in Linux so it will support DSPU
(Down Stream Physical Unit) protocols and activation sequences. OS/2
workstations and some of the newer versions of RUMBA actually look like PU's
on the network and require a DSPU activiation sequence if you are emulating
either a PU2 or PU4 type device. You will also need the IBM 3174 Cluster
Controller programmers reference, because in order to actually talk to all
these devices, you need to coordinate the SNA command sequence with the LLC
sequence (for example, a SABME under LLC8022 gets sent in response to an
ACTPU command from the host, etc.) . I have a complete SNA parser/builder,
WSF parser/builder, and DSPU router I wrote for a public domain project with
a guy at CMU on Netware, NT, and Unix about 12 years ago while I was with
Memorex Telex that provides 3174 emulation for SDLC, LLC8022 and Local
Channel interconnect. I could rumage around and try to find the code. . I
worked for memorex designing SNA software and hardware for their mainframe
products in the late 80's, early 90's and know SNA pretty well. I wrote the
SNA engine in their TN3270 and 3174 and 3088 protocol engines, and designed
the channel interface for some of their cluster controllers and comm
equipment. If you are trying to create a 3088 (3172) style TCPIP router for
an IBM host, this is a much simpler project than 3174 over LLC8022, but it
does require a Channel interface to ther host. 3174 emulation is a real
wooly bear depending on what features you want and the range of devices you
want to support. Linux needs a good 3174 engine. At some point, I was
going to write one after we got some killer clustering our on Linux, but I
love the idea of someone out there working on one. Would you like some help
from me?
Hope this helps.
Jeff
----- Original Message -----
From: <jonathan.naylor@socgen.com>
To: <linux-kernel@vger.rutgers.edu>
Cc: <Folkertvan.Heusden@wang.com>
Sent: Friday, September 10, 1999 6:59 AM
Subject: Re: SNA
> Hello Folkert
>
> > Anyone working on an SNA protocol stack for Linux?
> > Yeah, I know about that Ice-product, but the mainframe
> > costed a ton, can't afford their product now.
>
> There was. A fellow in Belgium had started to write a stack
> to support LU2 3270 sessions to allow terminal access to his
> mainframe. The 802.2 LLC code in the kernel is part of his
> work. However it was never finished because they installed
> TCP/IP on the mainframe and he was able to TELNET into it,
> maybe using x3270 I forget. That was all about two years ago.
> Unfortunately I haven't got his name or e-mail address handy.
>
> > Oh, and if nobody's working on such a thing; is there
> > any documentation on where to start when implementing
> > a protocol-stack? I guess I should add things to net/ and
> > update the protocols.c/Makefile, but after that I get
> > stuck :-)
> > Any help (also like "look at that stack; it's so simple and
> > basic, it's a good start") is welcome!
>
> I would suggest the nearest protocol in the existing stacks is
> X.25, a VC based protocol. For my sins I wrote it originally,
> maybe a clone and modification of that stack would be the
> easiest path, certainly X.25 is closer to SNA than (say) TCP/IP.
>
> > Thanks in advance,
> > Folkert van Heusden
>
> Feel free to chat about it with me on e-mail.
>
> > p.s. send a copy of your reply since I'm not on this
> > list - the traffic is waaaay to high :-/
>
> Will do.
>
> Jonathan
>
>
**************************************************************************
> The information contained herein is confidential and is intended solely
> for the addressee(s). It shall not be construed as a recommendation to
> buy or sell any security. Any unauthorized access, use, reproduction,
> disclosure or dissemination is prohibited.
>
> Neither SOCIETE GENERALE nor any of its subsidiaries or affiliates
> shall assume any legal liability or responsibility for any incorrect,
> misleading or altered information contained herein.
>
**************************************************************************
>
>
>
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.rutgers.edu
> Please read the FAQ at http://www.tux.org/lkml/
>
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/