powell@newyork.crd.ge.com (04/24/91)
I am an engineer and I have the task of trying to develop a system for mechanical engineering design that involves running programming tools such as fortran turbine design programs, compressor design programs, a C database, and a rule system(s) on different platforms. These platforms are IBM PC 386 or higher, Sun 4, HP, Decstation, and Vaxstation. All of my platforms are connected by TCP over ethernet. My problem is which communication software do I use to develop the client-server concept to run on each machine. I would appreciate any and all comments that would enlighten me about the pluses and minus of any given approach. Below I have listed some approaches that I have read about but need clarification from you more experienced software experts on the net. 1. I read about Sun's RPC which are suppose to allow the developer to concentrate on the application and not the network software. These sounded great in principle but is public domain RPC code available for the Vax (VMS and Unix lines) along with the IBM PC and HP. If yes then where can I get it? Suns manual says that RPC's have been run on these machines. To confuse me further, I understand that HP has a different version of RPC's then Suns. Does this mean that there are two different emerging standards? If yes then which is the one that appears to me winning? Does each competitor also support the others standard? 2. Berkley sockets vs System 5 sockets. Should I deal at the socket level and which type of sockets should I use? To run a program on a IBM PC from a Sun which type of sockets do I need on the IBM PC. Do sockets come for free with the TCP, and if yes then which type of sockets are they, and does a software developer have access to the TCP library needed to use these sockets? I appreciate any knowledge or pointers that I can use for helping me fill out my knowledge so that I can concentrate on the best approach to my problem. I have obtianed the Unix Network Programming book by Stevens. The book is excellent in describing the berkley sockets and TLI but I am not sure about which to use or if they are at all applicable when I have a VMS machine. Regards Dave
janzen@mprgate.mpr.ca (Martin Janzen) (06/05/91)
In Sun-Spots-Digest v10n86, powell@newyork.crd.ge.com (Dave Powell) writes: >[...] >1. I read about Sun's RPC which are suppose to allow the developer to > concentrate on the application and not the network software. These sounded > great in principle but is public domain RPC code available for the Vax > (VMS and Unix lines) along with the IBM PC and HP. If yes then where can I > get it? Suns manual says that RPC's have been run on these machines. Well, it's not public domain, but it is available and I'm pretty sure that it may be distributed freely. To get it, try writing to: Portable ONC/NFS Sun Microsystems, Inc MS 12-33 2550 Garcia Avenue Mountain View, CA 94043 or try nfsnet@sun.com. I'm using it right now for a telecommunications application which sends alarm information from a microVAX to a Sun, and it works great! It even writes code automatically to convert my data structures to XDR (eXternal Data Representation) format, so I don't have to worry about byte ordering, etc. Highly recommended. > To confuse me further, I understand that HP has a different version of > RPC's then Suns. Does this mean that there are two different emerging > standards? If yes then which is the one that appears to me winning? Does > each competitor also support the others standard? I don't know anything about this. Any HP-ers on Sun-Spots?? :-) >2. Berkley sockets vs System 5 sockets. Should I deal at the socket level > and which type of sockets should I use? To run a program on a IBM PC from > a Sun which type of sockets do I need on the IBM PC. Do sockets come for > free with the TCP, and if yes then which type of sockets are they, and > does a software developer have access to the TCP library needed to use > these sockets? I'd say don't deal at the socket level if you can help it. RPC saves you a lot of work: it packages up requests, handles XDR encoding and decoding of arguments and results, and can even write simple client/server code for you (using rpcgen). I've never used System V sockets, so I can't compare the two. Berkeley sockets certainly seem to be more widely used, though. If you must use sockets to communicate between Suns and PCs, you can use Sun's PC-NFS product. It provides a Berkeley socket interface, which I've used successfully to communicate from PC to Sun, as well as from PC to VAX. Caveat: If your PC application runs under Microsoft Windows, get something like FTP Software's PC-TCP instead; Sun PC-NFS won't work -- at least not the version I tried last year. PC-TCP also provides Berkeley sockets, as well as code for telnet, rcp, and other protocols. FTP's number is (617) 246-0900. Or, try comp.protocols.tcp-ip.ibmpc; I've seen posts from FTP people there. Both PC-NFS and PC-TCP come with RPC implementations. -- Martin Janzen janzen@mprgate.mpr.ca (134.87.131.13) MPR Teltech Ltd. Phone: (604) 293-5309 8999 Nelson Way Fax: (604) 293-6100 Burnaby, BC, CANADA V5A 4B5