Xref: utzoo comp.dcom.modems:2524 comp.mail.uucp:1966 Path: utzoo!attcan!uunet!husc6!uwvax!rutgers!bellcore!clyde!watmath!onfcanim!dave From: dave@onfcanim.UUCP (Dave Martindale) Newsgroups: comp.dcom.modems,comp.mail.uucp Subject: Re: UUCP g stats Message-ID: <16257@onfcanim.UUCP> Date: 25 Sep 88 19:14:13 GMT References: <183@arnold.UUCP> <1988Sep20.184054.2403@utzoo.uucp> <184@arnold.UUCP> <1988Sep25.015301.768@utzoo.uucp> Reply-To: dave@onfcanim.UUCP (Dave Martindale) Organization: National Film Board / Office national du film, Montreal Lines: 18 >90% of 1200 baud is 108 cps. Back when most of our news traffic >was at 1200, we saw uucp running at 109 +- 2 or so cps for hours on end, >quite consistently, for most sites. Uucico, unless you've modified it, always uses 64-byte packets. The g-protocol header is 6 bytes, so if there are always characters being transmitted with no "dead" periods, you would expect to see 64/70 = 0.914 of the modem bandwidth being useful data. 1200 bps = 120 cps; the "data" portion of this is 109.7 cps. Any more than this and you have inaccurate timing (i.e. timing a short file when the last buffer has been written but not yet arrived at the far end) or a too-fast UART clock. Any less and the host is probably not keeping up. With modems like the Trailblazer, the limiting factor seems to be hosts that can't handle continuous input and output at 19.2 Kbps more often than the modems.