nanog mailing list archives
Re: why upload with adsl is faster than 100M ethernet ?
From: Alex Bligh <alex () alex org uk>
Date: Fri, 15 Oct 2004 13:24:36 +0100
--On 15 October 2004 13:33 +0200 Iljitsch van Beijnum <iljitsch () muada com> wrote:
However, the cause can also be rate limiting. Rate limiting is deadly for TCP performance so it shouldn't be used on TCP traffic.
Add "unless appropriate shaping is performed prior to the rate-limiting with the parameters carefully tuned to the rate-limiting" You can also see an effect similar to rate-limiting from inadequate buffering where there is a higher input media speed than output. I can't remember what the tool is now, but there used to be a tool which worked like ping but sent a udp stream at a given rate per second and told you about packet drops, and also allowed for some parameter to be tweaked to give stochastic variation in interpacket delay (i.e. massive jitter). You could use this to show inadequate buffering on gigabit interfaces where a 2Mb/s stream would get through, but if you wound up the jitter sufficiently, a whole burst of packets would arrive together and a gigabit interface with (deliberately) misconfigured buffers would then drop packets. Alex
Current thread:
- why upload with adsl is faster than 100M ethernet ? Joe Shen (Oct 14)
- Re: why upload with adsl is faster than 100M ethernet ? Mikael Abrahamsson (Oct 14)
- Re: why upload with adsl is faster than 100M ethernet ? Jay Hennigan (Oct 14)
- Re: why upload with adsl is faster than 100M ethernet ? Joe Shen (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Iljitsch van Beijnum (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Joe Shen (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Iljitsch van Beijnum (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Alex Bligh (Oct 15)
- RE: why upload with adsl is faster than 100M ethernet ? Mike McSpedon (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Gordon (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Marc Binderberger (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Andy Dills (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Alex Bligh (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Andy Dills (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Alex Bligh (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Alexei Roudnev (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? sergei (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Joe Shen (Oct 15)
- Re: why upload with adsl is faster than 100M ethernet ? Marc Binderberger (Oct 15)