Path: csiph.com!feeder.erje.net!2.us.feeder.erje.net!bloom-beacon.mit.edu!bloom-beacon.mit.edu!panix!not-for-mail From: Grant Edwards Newsgroups: comp.arch.embedded Subject: Re: UDP Terminal Protocol Date: Tue, 13 Dec 2016 15:16:12 +0000 (UTC) Organization: PANIX Public Access Internet and UNIX, NYC Lines: 41 Message-ID: References: <7phv4cd0dickoubm7k7rud6or7vtnft8rb@4ax.com> NNTP-Posting-Host: 67-130-15-94.dia.static.qwest.net X-Trace: reader1.panix.com 1481642172 7660 67.130.15.94 (13 Dec 2016 15:16:12 GMT) X-Complaints-To: abuse@panix.com NNTP-Posting-Date: Tue, 13 Dec 2016 15:16:12 +0000 (UTC) User-Agent: slrn/1.0.2 (Linux) Xref: csiph.com comp.arch.embedded:25561 On 2016-12-13, Robert Wessel wrote: > OTOH, it's clear that a number of people have implemented a UDP-based > protocol for handling the sort of things often done with a serial > console attached to a device. This has a number of advantages - you > can fake UPD over Ethernet with very little code, especially if you > define away things like fragmentation and options. A simplified > TELNET-ish protocol on top of that would be pretty simple, you just > need some basic packet sequencing and acknowledgements. I know of people who have implemented that on top of IP rather than UDP. They call it TCP. ;) > IOW, something with a relationship to TELNET sort of like TFTPs > relationship to FTP. Just use a raw TCP connection. There's no need to implement the TELNET protocol at all. The Unix command line client will skip all the handshaking stuff if you use a non-standard port. Or you can use netcat. Or any number of terminal emulators or COM port redirectors that support raw TCP connections. If you're on a local Ethernet segment, just use raw UDP. I've been using both those approaches for close to 20 years, and have never had any problems. > OTOH, despite looking, I just don't see any standards for doing that > sort of thing. Am I just missing it? Is there a defacto standard > even if there's no RFC? If you want something reliable that works over WANs, use TCP: it's the only way you're going to dependably make anything work through a firewall. If you're going to assume local Ethernet, you can just use UDP. -- Grant Edwards grant.b.edwards Yow! Gee, I feel kind of at LIGHT in the head now, gmail.com knowing I can't make my satellite dish PAYMENTS!