chris@uunet.uu.net (Chris Jankowski) (06/14/89)
I am evaluating feasibility of the following setup: Public Sun workstation Data Network Sun workstation ____________^______________ _____^______ ____________^_____________ / \ / \ / \ INGRES-NET SunLink X.25 PDN SunLink X.25 INGRES-NET appl. rexec <-> TCP/IP <-> X.25 <-> X.25 PDN <-> X.25 <-> TCP/IP <-> rexec appl. One of the Suns is to be based in Europe, the other in Australia. INGRES-NET I am told issues rexec calls to the remote peer. They are encapsulated into TCP/IP datagrams and then passed to SunLink X.25 software which sends them as X.25 packets out to a PDN interface (9.6 kb/s synchronous). On the other end SunLink X.25 retrieves TCP/IP packets. They then deliver the rexec information to INGRES-NET on the other end. (In fact the other INGRES-NET does not have to run on the Sun - it may run on another UNIX host on the local network.) In principle everything should work fine. But there are countless questions. What about virtual call establishment and clearing? With the distance involved just keeping the call open when not needed may be quite costly. Is the SunLink software smart enough to open such a call automatically after receiving first packet to be forwarded trough the link? What about delays? Won't that timeout in any of the higher layers? By the way I know that the TCP/IP to X.25 conversion can be done in a hardware box (CS/150 will do I think). Use of Sun workstations is much prefered in this case as they will be there anyway to run some other applications. Only if this setup does not work another solution may be considered. I am pretty sure somebody tried similar setup before. Dear netters, I will greatly appreciate your comments, descriptions of your experiences (both positive and negative), pointers to other sources of information etc. I prefer to receive responses by email. I will summarize to the net. Chris Jankowski chris@yarra.oz.au chris@yarra.oz Pyramid Technology Australia - Melbourne