pwb@newt.phys.unsw.OZ.AU (Paul W. Brooks) (02/22/91)
Could someone (or several someones :-) ) please point me to some documentation, specs, etc. on the LAT protocol over ethernet? I am thinking of writing a terminal emulator to run on a PC platform, possibly TSR and background-running, and in this environment I thought it would be nice to talk LAT directly. I tried to RT (relevent)FM for my Ultrix node, but couldn't find anything that would help with the implementation. So: 1) Is the protocol published somewhere, or is it proprietary? 2) If proprietary, is there any way I could obtain the specs anyway (:-) Its worth a try!) 3) Does anyone have any comments, suggestions or pointers to a previously written implementation so I might not have to roll-my-own? Please email me, and I'll summarize later. Thanks in anticipation, Paul Brooks |Internet: pwb@newt.phys.unsw.edu.au Uni. of N.S.W. |If you have trouble sleeping, try lying on the end of Kensington NSW 2033| your bed. With a little luck you'll drop off. AUSTRALIA | - Mark Twain.
pwb@newt.phys.unsw.OZ.AU (Paul W. Brooks) (03/16/91)
Thanks to all who replied to my request a few weeks ago on the LAT protocol. Here is the summary of replies. I hope to have something running shortly! From: lstowell%pyrnova.pyramid.com@munnari.oz (Lon Stowell) } DEC has finally decided that LAT is proprietary and licenseable } technology. I haven't heard yet whether this means they will } actually publish the specs in a comprehensible format or not. } Hopefully you will get FTP sources for drivers etc. from your } posting. [ I didn't :-) ] From: "Kevin Oberman, LLNL, +1 415-422-6955" <OBERMAN@icdc.llnl.gov> } LAT is both proprietary and patented. Licenses are available, but the pricing } is aimed at commercial implementors. I believe the base price is in the $10K } range. The only way to get documentation is to license the protocol from DEC. } It's a pretty simple protocol and was reverse engineered by several companies } before the patents were granted. Some of these companies have bought licenses, } others are being sued for patent infringment. Some may have dropped the } products in question.(There is nothing illegal about selling a patentable item } before the patent is granted, but you have to stop as soon as it is.) } LAT for PCs is available from many vendors including Datability. I have no } experience with any non-DEC implementation. From: ken@pluto.dss.com (Ken Adler) } Yes Lat is proprietary to DEC. Reverse engineering it is a somewhat } involved project. There are a few companies that already have reversed } engineered and have it available in a number of forms. Datability is one } company. We use the LAT in our PC based products, our Terminal/Communication } Server HArdware, and our Unix based LAT services product. } Good Luck. If I can of any help, please let me know. [Thanks. I will be in touch shortly] From: "Franz Schoenbauer, Computer Science," } Well, we have done this just in the last few weeks. We were unable to get any } specs and tried to reverse-engineer the protocol by tapping an ethernet line } and watching the packets go back and forth. Not very nice. But we ended up } with something that does at least work. The program makes a vax pretend it } is a terminal server. Embedded in the program is the protocol, mostly uncovered } by educated guesses and a few packet types still completely unclear, but } terminal emulation works. } If you are interested i'm willing to make the source available (FTP). } On the other hand if somebody points you to any reference, please let me know, } we'd be feeling better if we knew what those strange packets are... A [Well, I didn't get any references to papers on LAT (as you can see) BUT I may have a pointer to a reference on packet types somewhere. I'll send the info when I find it] Thanks, Franz [ Thank you ] From: Joerg Stadler <joergs@cat.de> } We use the latest version of KERMIT as terminal emulator with the LAT } protocol. On the PC, we have DEC's DECNET for DOS software, which includes } a LAT driver. After starting LAT on the PC, one can use the KERMIT command } 'SET PORT DECNET <node>' to start a terminal session with an arbitrary on the } net. } Hope this helps. [Thanks for the info. Depending on how memory hungry it is, and whether it can be made memory-resident on a PC, I may use this approach.] From: Roger Ivie <SLSW2%cc.usu.edu@munnari.oz> > 1) Is the protocol published somewhere, or is it proprietary? } It's proprietary. Several years ago DEC decided to license it since people } were writing things to talk to it anyway; at that time they were charging } something on the order of $10,000 for a license. } Roger Ivie [ Thanks. Isn't it a good think other licenses (car, boat, etc) aren't that much!] From: A deviant having fun ! 04-Mar-1991 1243 <cleary@crocky.enet.dec.com> >> 1) Is the protocol published somewhere, or is it proprietary? } The protocol is proprietary but has been reversed engineered several } times. >> 2) If proprietary, is there any way I could obtain the specs >>anyway (:-) Its worth a try!) } Yes. It is available under a variety of licenses. These include a } reference implementation in C. Write to Robert Schlelein who is the } licensing manager. He is reachable by email at : } schleelein@delni.enet.dec.com } and by paper at: } Robert Schleelein } Digital Equipment Corp. } 550 King Street (LKG2-1/X2) } Littleton, MA 01460-1289 } Ph: 508-486-7017 } FAX 508-486-7417 >> 3) Does anyone have any comments, suggestions or pointers to a >>previously written implementation so I might not have to roll-my-own? } There are a few implementations which I know of. Most are commercial } ones rather than public domain. A company called Meridian has a product } called SuperLAT which is a portable toolkit for rolling your own. } Contact is Don Hirsh at 314-532-7708. [ This is the definitive reply from the man at DEC!] Thanks also to the following for posting with essentially the above information: gerhardt@kalvin.enet.dec.com bruce@camb.com (Barton F. Bruce) In short, ladies and gentleman, it is proprietary, for $10K (presumably $US !) it can be yours, or it can be done that hardway and you may or may not be sued!. Thanks again for everybodies help. Let the Project begin.!! Paul Brooks |Internet: pwb@newt.phys.unsw.edu.au Uni. of N.S.W. |If you have trouble sleeping, try lying on the end of Kensington NSW 2033| your bed. With a little luck you'll drop off. AUSTRALIA | - Mark Twain.