[HECnet] TCP/IP experts?

On 2013-02-17 02:41, Clem Cole wrote: On Sat, Feb 16, 2013 at 8:12 PM, Johnny Billquist <bqt at softjar.se <mailto:bqt at softjar.se>> wrote: I honestly don't know for sure, but this is the first I've ever heard of that. Doing a "portable" stack for RSX would probably be very hard, by the way. Actually doing a portable stack was hard for any OS, but that was idea. True. Portable do have its advantages. But it always comes at a price, and for something like RSX, that price is probably way too high. There are big discrepancies in the I/O model, memory management as well as process handling and god knows what else... It was written originally in C by Rob Gurweitz and some other ??Bob Walsh maybe?? - I want to say in 1978/79 time frame, using the original Ritchie compiler. There were a ton of tools developed in the UNIX community to move code at the assembler lever from V6/V7 to RT11 & RSX. Look at the old Harvard tape that I think Warren has in his archives if you are interested. I do not remember how it moved the HP's, but there must have been an 3000 or 1000 hack for the Ritchie compiler at HP and/or Berkeley. C would definitely not been an option at that point. Not in the RSX world. I don't even think DECUS C had been published, and that compiler have some serious limitations. As for the BBN portable IP/TCP stack, it is where the famous "mbuf" structure came from. Rob needed an OS independent memory system for incoming packets. The BBN IP/TCP was written to call it, and then on a kernel for kernel basis the mbuf system was written for the native OS. mbufs makes a lot of sense. I did something similar for my TCP/IP. ... you want really bad performance, you want to be close to the kernel, That was not an goal. You have to remember that at the time of IP's development, every computer firm had it's own proprietary networking scheme. DARPA wanted something that worked on all them, so they paid to have it created and implemented. But it also meant that DARPA needed those implementations of IP/TCP for the system that their primary folks were using - the PDP-10, Multics, UNIX. In some labs (like US Army's BRL if IIRC), there were realtime systems doing specific tasks. HP and DEC were the two firms selling those systems. So BBN needed an implementation of IP that >>worked<< that allowed those systems to connect. Right. But thinking a bit more, I'm pretty sure there was no TCP/IP for RSX. You even have all those old RFCs with comments and lists about systems available, and implementations... I've been over them a few times. I'm pretty sure RSX is not in there. When we finished it, some of my friends/former colleagues at CMU/CS asked me for it, we made it available (no stinking GPL, or calling it "open source" - we just shared it). They wrote the mail 11 interface and cleaned the whole thing up a great deal. Open source and free software is not what it used to be. I know... :-( Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol