[45792] in North American Network Operators' Group
Re: Cisco PPP DS-3 limitations - 42.9Mbpbs?
daemon@ATHENA.MIT.EDU (Stephen J. Wilcox)
Wed Feb 20 11:09:27 2002
Date: Wed, 20 Feb 2002 16:08:47 +0000 (GMT)
From: "Stephen J. Wilcox" <steve@opaltelecom.co.uk>
To: Randy Bush <randy@psg.com>
Cc: nanog@merit.edu
In-Reply-To: <E16dYsz-000FIc-00@rip.psg.com>
Message-ID: <Pine.LNX.4.21.0202201602350.13061-100000@staff.opaltelecom.net>
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Hmm, reasonable explanation..
presumably this can be improved (a little) with increased interface
buffers.. ? and possibly non fifo queuing eg custom queuing in favour of
TCP rathen than UDP/ICMP etc which wont have the backoffs
Cheers
Steve
On Wed, 20 Feb 2002, Randy Bush wrote:
> > we run HDLC on DS3 and we max at about 40.something too
>
> if you're using five min (or three min) samples, and you're seeing 70%,
> peaks are likely much higher and some users' packets are being dropped.
> by 80%, enough packets are being dropped that users are likely to see
> the effects of exponential backoff. things do not improve above 80%.
>
> randy
>
--
Stephen J. Wilcox
IP Services Manager, Opal Telecom
http://www.opaltelecom.co.uk/
Tel: 0161 222 2000
Fax: 0161 222 2008
