Date: Fri, 1 Nov 1996 10:07:17 -0500 From: Garrett Wollman <wollman@lcs.mit.edu> To: Greg Lehey <grog@lemis.de> Cc: joerg_wunsch@uriah.heep.sax.de, FreeBSD-current@FreeBSD.org (FreeBSD current users), isdn@muc.ditec.de (FreeBSD ISDN Distribution List) Subject: Re: Any ISDN-BRI cards work under FreeBSD? Message-ID: <9611011507.AA28746@halloran-eldar.lcs.mit.edu> In-Reply-To: <199611010828.JAA19837@freebie.lemis.de> References: <199610311858.TAA16867@uriah.heep.sax.de> <199611010828.JAA19837@freebie.lemis.de>
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<<On Fri, 1 Nov 1996 09:28:40 +0100 (MET), Greg Lehey <grog@lemis.de> said: > The good news, however, is that 56 kb/s is not the only game in town. > It was only ever intended as an interim measure, and many areas supply > 64 kb/s. Could somebody in the US please comment? Most interoffice trunks in the US no longer use in-band signalling, so most ISDN-capable end offices will deliver a full 64-kb data path, and data calls are supposed to fail if there is not a 64-kb path. Voice calls will still succeed, with the missing bit thrown out (I think it gets forced to zero by the time you see it). The 56-kb service was only ever used for old, voice-engineered T-1 trunks, which did not have any sort of signalling associated with them. As more and more of the network has switched to SS#7, this has been rapidly disappearing, and now interoffice signalling is sent on a separate trunk. You can check the archives of TELECOM Digest for more information on this topic. -GAWollman -- Garrett A. Wollman | O Siem / We are all family / O Siem / We're all the same wollman@lcs.mit.edu | O Siem / The fires of freedom Opinions not those of| Dance in the burning flame MIT, LCS, ANA, or NSA| - Susan Aglukark and Chad Irschick
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