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AT&T MPLS / BIB Routers

What type of hardware are they using for this BIB router?


-----Original Message-----
From: Mikeal Clark [mailto:mikeal.clark at gmail.com] 
Sent: Wednesday, February 16, 2011 6:16 PM
To: Jim Gettys
Cc: nanog at 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 at 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 
>> experience with the "Business in a Box" routers they are using for 
>> our smaller sites.  We are seeing extremely high latency under load.

>> Anyone have any experience with these devices that could shed some 
>> light on this?  Are they really this bad?
> There is excessive buffering in all sorts of devices all over the
> This causes high latency under load (along with higher packet losses, 
> and lots of other problems.
> It's what I've been blogging about on http://gettys.wordpress.com. 
> These buffers fill; and they are so large they have defeated TCP 
> 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
>        o some corporate and ISP networks run without AQM, in 
> circumstances that they should.
>        o Windows, Mac OSX and Linux all have bufferbloat in their 
> 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 
> defeating slowstart.
> Come start helping fix this: please join us at bufferbloat.net, as we 
> try to get people to fix it.  Already there are some experimental 
> patches for the Linux Intel wireless driver.
>                        Jim Gettys
>                        Bell Labs