[19670] in North American Network Operators' Group
Re: And we thought the text part of the Starr Report would be bad
daemon@ATHENA.MIT.EDU (Miquel van Smoorenburg)
Mon Sep 21 16:29:40 1998
To: nanog@merit.edu
From: miquels@cistron.nl (Miquel van Smoorenburg)
Date: 19 Sep 1998 22:39:15 +0200
In article <199809182139.RAA10174@us.net>, David Stoddard <dgs@us.net> wrote:
> There is more to this than meets the eye -- 28.8K is asynchronous
> and has start and stop bits for every byte, so there are a maximum
> of 2880 bytes/sec available over 28.8K. Then there is the issue
Almost every modem supports V42 error correction, which makes the modems
speak a sort of synchronous with each other (actually data is transmitted
in blocks with a start-of-block and end-of-block marker, and a checksum).
That gets you 8 bits in a bith minus some negligeble V42 overhead.
So an 28k8 modem can actually transfer almost 3.6 Kbytes/sec.
Because of the block-oriented approach you do get a bit higher latency
on interactive connections, which is why gamers often turn of V42.
Somehow, nobody seems to know this.
Mike.
--
"Did I ever tell you about the illusion of free will?"
-- Sheriff Lucas Buck, ultimate BOFH.
