mcia@uhura.cc.rochester.edu (Mike Ciaraldi) (11/07/90)
I'm trying to set up a gateway system to route between workstations connected by Ethernet and an IBM mainframe host connected by a 56kb line running SNA/SDLC. What I have working now is a Sun 4/330 with a Systech communications board and software from SSI. The software provides 3270 terminal emulation and 3770 RJE emulation. The custom routing software uses something from SSI called "HLLAPI", the High Level Language Applications Program Interface. This gives us a standard set of subroutines for sending keystrokes, querying fields on the emulated 3270 screen, etc. I've been able to handle 200+ simultaneous 3270 sessions, plus card reader, punch, and printer emulation like an RJE terminal. I'm looking for a hardware/software solution that provides the same functionality, but with lower performance (say, 20 sessions) and cost. The comm board we use is only available for the VMEbus, so we can't plug it into a SPARCstation. I found some comm boards for the S-bus that provide synchronous communications, but so far haven't found one that provides HLLAPI compatiblity or RJE. What I don't need is a package that just opens a 3270 emulation screen on a Sun screen; I need to get to the emulated screens from my program so I can digest them and send them to the workstations. Right now I'm mostly interested in a Sun-based solution, but I'd consider other platforms if porting my HLLAPI-based C code wouldn't be too hard. And I need RJE support, of course. Any suggestions? Anyone done something similar? BTW, is there a newsgroup that would be a better choice? Thanks. Mike Ciaraldi ciaraldi@uhura.cc.rochester.edu ...rochester!uhura!ciaraldi
tom@gatech.edu (Tom Wiencko) (11/11/90)
In article <14474@accuvax.nwu.edu> mcia@uhura.cc.rochester.edu (Mike Ciaraldi) writes: >I'm trying to set up a gateway system to route between workstations >connected by Ethernet and an IBM mainframe host connected by a 56kb >line running SNA/SDLC. There are about 547 ways to do this. I'll outline a few. >What I have working now is a Sun 4/330 with a Systech communications >board and software from SSI. The software provides 3270 terminal >emulation and 3770 RJE emulation. The custom routing software uses >something from SSI called "HLLAPI", the High Level Language >Applications Program Interface. This gives us a standard set of >subroutines for sending keystrokes, querying fields on the emulated >3270 screen, etc. HLLAPI is just the programmatic way of getting into the SNA data stream. This is not a protocol by itself, it is merely IBM doublespeak for an interface library to the communications subsystem. >I've been able to handle 200+ simultaneous 3270 sessions, plus card >reader, punch, and printer emulation like an RJE terminal. >I'm looking for a hardware/software solution that provides the same >functionality, but with lower performance (say, 20 sessions) and cost. The easiest way to do this is to equip your mainframe with TCP/IP and run TN3270 across your Ethernet (or Token Ring) to a 3172 controller. Alas, this is not an SNA solution. A lot depends on what devices are where: are the workstations local to the mainframe, or are they remote (you imply that they are remote). If they are remote and you absolutely must have an SNA link, the problem is different. You would need some device which can act as a gateway from your workstations to SNA. You can do this with Token Ring with a 3174 remote controller, but I don't believe this works on Ethernet. There are several third parties who have other gateway solutions, but as I tend to live in an IBM world, I have no names handy (but SSI could probably point you in the right direction). >The comm board we use is only available for the VMEbus, so we can't >plug it into a SPARCstation. I found some comm boards for the S-bus >that provide synchronous communications, but so far haven't found one >that provides HLLAPI compatiblity or RJE. >What I don't need is a package that just opens a 3270 emulation screen >on a Sun screen; I need to get to the emulated screens from my program >so I can digest them and send them to the workstations. This does make things more complicated. This is a good reason to try to do this with TCP/IP, as most TCP/IP implementations come with a socket library which would allow you to do this easily. >Right now I'm mostly interested in a Sun-based solution, but I'd >consider other platforms if porting my HLLAPI-based C code wouldn't be >too hard. And I need RJE support, of course. IBM's RS/6000 has a thing called SNA Services which might be just the ticket. It supports this stuff six ways from Sunday. It has *no* application code with it (it is just an API) so you can roll your own any way you want. If you want RJE or 3270 emulation, you can get software to do that from SSI or TPS (I can get you addresses and phone numbers on request). >Any suggestions? Anyone done something similar? BTW, is there a >newsgroup that would be a better choice? Thanks. comp.protocols.ibm maybe? Tom Wiencko & Associates, Inc. (404) 977-4515 {backbone}!emory!stiatl!vta!wiencko!tom