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Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that
From: Aled Morris via NANOG <nanog () nanog org>
Date: Mon, 27 Jan 2020 12:42:28 +0000
On Mon, 27 Jan 2020 at 12:13, Rob Pickering <rob () pickering org> wrote:
Wasn't the 56/64k thing a result of CAS (bit robbed) signalling which was a fudge AT&T did to transport signalling information in-band on T1s by stealing the low order bit for OOB signalling (it wasnt actually every low order bit, but meant you had to throw away every low order bit as CPE didn't know which ones were "corrupted" by the carrier). Proper ISDN was always 64kbit/s clear path with separate D channels carried OOB end to end, away from the B channel data.
There was some element of interoperability required with the pre-existing data network architecture based on 56k channels and T1 bearers. This article has the detail: https://en.wikipedia.org/wiki/T-carrier *Soon after commercial success of T1 in 1962, the T1 engineering team realized the mistake of having only one bit to serve the increasing demand for housekeeping functions. They petitioned AT&T management to change to 8-bit framing. This was flatly turned down because it would make installed systems obsolete.* Compared to what was to follow, that all had to suffer the 56k channel limitation, there can't have been that many installed systems in 1962! Aled
Current thread:
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that, (continued)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Karl Auer (Jan 25)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Paul Ebersman (Jan 25)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that bzs (Jan 26)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Bruce H McIntosh (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Ben Cannon (Jan 28)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Joly MacFie (Jan 25)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Bryan Holloway (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Saku Ytti (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Mark Andrews (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Rob Pickering (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Aled Morris via NANOG (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Bryan Holloway (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Aled Morris via NANOG (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Lyle Giese (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Lyle Giese (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Roy (Jan 27)
- RE: Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Jamie Bowden via NANOG (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Brandon Martin (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Bryan Holloway (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that bzs (Jan 27)
- Re: Reminiscing our first internet connections (WAS) Re: akamai yesterday - what in the world was that Forrest Christian (List Account) (Jan 28)