[137587] in North American Network Operators' Group
RE: AT&T MPLS / BIB Routers
daemon@ATHENA.MIT.EDU (Ryan Finnesey)
Thu Feb 17 09:21:02 2011
Date: Thu, 17 Feb 2011 06:19:57 -0800
In-Reply-To: <AANLkTikLo-kn7Zmu=jOVXnQLKzWfHK5jZFTrajEpNC8h@mail.gmail.com>
From: "Ryan Finnesey" <ryan.finnesey@HarrierInvestments.com>
To: "Mikeal Clark" <mikeal.clark@gmail.com>, "Jim Gettys" <jg@freedesktop.org>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
What type of hardware are they using for this BIB router?
Cheers
Ryan
-----Original Message-----
From: Mikeal Clark [mailto:mikeal.clark@gmail.com]=20
Sent: Wednesday, February 16, 2011 6:16 PM
To: Jim Gettys
Cc: nanog@nanog.org
Subject: Re: AT&T MPLS / BIB Routers
I'm building up to 3000-4000ms latency with these BIB routers. We never
had this issue on the old point to points using Cisco gear.
On Wed, Feb 16, 2011 at 5:09 PM, Jim Gettys <jg@freedesktop.org> wrote:
> On 02/16/2011 05:44 PM, Mikeal Clark wrote:
>
>> We just put in a AT&T MPLS and are having a pretty negative=20
>> experience with the "Business in a Box" routers they are using for=20
>> our smaller sites. We are seeing extremely high latency under load.
>> Anyone have any experience with these devices that could shed some=20
>> light on this? Are they really this bad?
>>
>>
> There is excessive buffering in all sorts of devices all over the
Internet.
> This causes high latency under load (along with higher packet losses,=20
> and lots of other problems.
>
> It's what I've been blogging about on http://gettys.wordpress.com.=20
> These buffers fill; and they are so large they have defeated TCP=20
> congestion avoidance to boot, with horrifying consequences.
>
> So far, I've found this problem (almost) everywhere I've looked:
> o ICSI has good data that bufferbloat is endemic in DSL, Cable,
> and FIOS. Delays are often measured in seconds (rather than
milliseconds).
> o some corporate and ISP networks run without AQM, in=20
> circumstances that they should.
> o Windows, Mac OSX and Linux all have bufferbloat in their=20
> network stacks, at a minimum on recent network device drivers, and
often elsewhere.
> o Every home router I've tested is horrifyingly bad.
> o 3g networks & 802.11 have this in spades.
>
> Why should AT&T's MPLS be any different?
>
> My next topic will be "transient" bufferbloat, having to do with=20
> defeating slowstart.
>
> Come start helping fix this: please join us at bufferbloat.net, as we=20
> try to get people to fix it. Already there are some experimental=20
> patches for the Linux Intel wireless driver.
> Jim Gettys
> Bell Labs
>
>
