nanog mailing list archives
Re: Clear Channel on a T1
From: "Majdi S. Abbas" <msa () samurai sfo dead-dog com>
Date: Thu, 22 Mar 2001 14:49:31 -0800
On Thu, Mar 22, 2001 at 10:19:35PM +0000, Ron Buchalski wrote:
Forcing the 8th bit to a '1' isn't done to maintain timing.
Huh?
The 8th bit was forced to a '1' to maintain ones density on the T1 line. Early T1 specs did not allow more than 15 consecutive zeros to be transmitted because the T1 repeaters along the line rely on periodic pulses to keep their oscillators active. It was not a problem for voice circuits,
Yes, and this was necessary to prevent those repeaters from losing sync -- thus maintaining timing. --msa
Current thread:
- Clear Channel on a T1 CARL . P . HIRSCH (Mar 22)
- Re: Clear Channel on a T1 Terrence Chatfield (Mar 22)
- Re: Clear Channel on a T1 Jason A. Mills (Mar 22)
- <Possible follow-ups>
- Re: Clear Channel on a T1 CARL . P . HIRSCH (Mar 22)
- Re: Clear Channel on a T1 Brett Frankenberger (Mar 22)
- Re: Clear Channel on a T1 Terrence Chatfield (Mar 22)
- RE: Clear Channel on a T1 Christian Kuhtz (Mar 22)
- Re: Clear Channel on a T1 Douglas A. Dever (Mar 22)
- Re: Clear Channel on a T1 Rachel Warren (Mar 23)
- Re: Clear Channel on a T1 Ron Buchalski (Mar 22)
- Re: Clear Channel on a T1 Majdi S. Abbas (Mar 22)
- Re: Clear Channel on a T1 Ron Buchalski (Mar 23)
- Re: Clear Channel on a T1 Ron Buchalski (Mar 23)
- Re: Clear Channel on a T1 Christopher A. Woodfield (Mar 23)
- Re: Clear Channel on a T1 lucifer (Mar 23)
- Re: Clear Channel on a T1 Peter Galbavy (Mar 26)
- Re: Clear Channel on a T1 Christopher A. Woodfield (Mar 23)