SNHAM@TTUVM1.BITNET ("Sarek: the logical one........") (01/16/88)
I recently interviewed with a company known as Mitek, Inc. based in Carrellton, Texas. They produce a 'box' that connects all kinds of work stations to just about anything else. They showed me how the could Telnet into an IBM 4341 from their VAX, and into a AT&T 3B2. Quite impressive. Apparently what they do is run software at each workstation that makes it look like a 3270 to the box. The box has an Ethernet side towards the work stations and looks like a 3274 to the IBM. It is QUITE capable of allowing users to logon to a VAX, TSO on their IBM, and run graphics at a Textronics station all at the same time. By the way, I haven't decided whether or not I'm going to work for them, but I was impressed by what they'd developed. Michael J. Hammel Student Assistant, Computer Network Services Texas Tech University SNHAM @ TTUVM1
littauer@amdahl.UUCP (Tom Littauer) (01/17/88)
In article <8801162207.AA26467@jade.berkeley.edu> "Sarek: the logical one........" <SNHAM%TTUVM1.bitnet@jade.berkeley.edu> writes: >Apparently what they do is run software at each workstation that makes it >look like a 3270 to the box. The box has an Ethernet side towards the work >stations and looks like a 3274 to the IBM. It is QUITE capable of allowing >users to logon to a VAX, TSO on their IBM, and run graphics at a Textronics >station all at the same time. This isn't what the previous poster was talking about. This case is fairly easy to do. I'd be *REAL* interested to see a 3270 looking like a glass tty. It's easy enough to do for line-at-a-time operation, but when you're looking for each character individually (like in vi) the poll delay, host interrupt rate, and bandwidth restrictions will kill you quick. Not to mention being forced to hit one of the "transmit" keys in addition to the keystroke you wanted (like "enter" or "PA1" or ...). If you folks find something that comes close, *PLEASE* let me know. We've struggled long and hard to make our Unix (tm AT&T) accessible to users with 3270 terminals. We've succeeded in most areas, but editors (for example) we've had to provide parallel solutions for. Interesting side note: "rn" (the news reading tool) is written for glass tty but runs OK on 3270 in our system - just to show that there are SOME applications that expect individual characters that work on 3270. Let me know if I can clarify this any more. Tom -- UUCP: littauer@amdahl.amdahl.com or: {sun,decwrl,hplabs,pyramid,ihnp4,ames,uunet,cbosgd}!amdahl!littauer DDD: (408) 737-5056 USPS: Amdahl Corp. M/S 330, 1250 E. Arques Av, Sunnyvale, CA 94086 I'll tell you when I'm giving you the party line. The rest of the time it's my very own ravings (accept no substitutes).
littauer@amdahl.amdahl.com (Tom Littauer) (01/17/88)
In article <8801162207.AA26467@jade.berkeley.edu> "Sarek: the logical one........" <SNHAM%TTUVM1.bitnet@jade.berkeley.edu> writes: >Apparently what they do is run software at each workstation that makes it >look like a 3270 to the box. The box has an Ethernet side towards the work >stations and looks like a 3274 to the IBM. It is QUITE capable of allowing >users to logon to a VAX, TSO on their IBM, and run graphics at a Textronics >station all at the same time. This isn't what the previous poster was talking about. This case is fairly easy to do. I'd be *REAL* interested to see a 3270 looking like a glass tty. It's easy enough to do for line-at-a-time operation, but when you're looking for each character individually (like in vi) the poll delay, host interrupt rate, and bandwidth restrictions will kill you quick. Not to mention being forced to hit one of the "transmit" keys in addition to the keystroke you wanted (like "enter" or "PA1" or ...). If you folks find something that comes close, *PLEASE* let me know. We've struggled long and hard to make our Unix (tm AT&T) accessible to users with 3270 terminals. We've succeeded in most areas, but editors (for example) we've had to provide parallel solutions for. Interesting side note: "rn" (the news reading tool) is written for glass tty but runs OK on 3270 in our system - just to show that there are SOME applications that expect individual characters that work on 3270. Let me know if I can clarify this any more. Tom -- UUCP: littauer@amdahl.amdahl.com or: {sun,decwrl,hplabs,pyramid,ihnp4,ames,uunet,cbosgd}!amdahl!littauer DDD: (408) 737-5056 USPS: Amdahl Corp. M/S 330, 1250 E. Arques Av, Sunnyvale, CA 94086 I'll tell you when I'm giving you the party line. The rest of the time it's my very own ravings (accept no substitutes).
VM0A61@WVNVM.BITNET ("Bryan, Jerry") (01/18/88)
>This isn't what the previous poster was talking about. This case is fairly >easy to do. I'd be *REAL* interested to see a 3270 looking like a glass >tty. It's easy enough to do for line-at-a-time operation, but when you're >looking for each character individually (like in vi) the poll delay, >host interrupt rate, and bandwidth restrictions will kill you quick. >Not to mention being forced to hit one of the "transmit" keys in >addition to the keystroke you wanted (like "enter" or "PA1" or ...). >If you folks find something that comes close, *PLEASE* let me know. >We've struggled long and hard to make our Unix (tm AT&T) accessible >to users with 3270 terminals. We've succeeded in most areas, but >editors (for example) we've had to provide parallel solutions for. There are at least two extremely good (if maybe not very cheap) solutions. The key is that any such support (in the IBM world, it is often called "reverse protocol emulation") must be able to see individual 3270 keystrokes. One solution is to put a black box (I cannot remember the name of a vendor right now, but there are two or three out there) on your co-ax between your IBM 3270 and your IBM controller. The black box will have a side ASCII port, which will then connect into your UNIX world, emulating a VT100 or whatever. The black box will also support connection down the co-ax into the IBM world. The other solution is to replace your older IBM 3274 controllers with newer IBM 3174 controllers, and to include ASCII ports into the UNIX world emulating VT100's. Other vendors (AT&T comes to mind) also support the same sort of thing in their 3270 lookalikes. This latter solution may not be all that expensive if you are just now putting in IBM terminals and controllers, but it may be expensive if you already have the 3274's. 3174's are quite inexpensive these days (much less expensive than DEC terminal servers, for example), but it is a "waste" is some sense to replace otherwise perfectly good 3274's with 3174's. Any terminal emulation which is on the inside of the IBM controller (in the host, for example) will have some or all of the problems you describe, and there is nothing that can be done about it. The problem is that only the controller sees individual keystrokes, and the terminal is presented to the host in block mode. Thus any really good emulation has to be in the controller or between the controller and terminal.