[151740] in North American Network Operators' Group
Re: Comcast Ethernet Feed
daemon@ATHENA.MIT.EDU (Brielle Bruns)
Thu Mar 29 20:47:45 2012
Date: Thu, 29 Mar 2012 18:47:11 -0600
From: Brielle Bruns <bruns@2mbit.com>
To: nanog@nanog.org
In-Reply-To: <30107560.1217.1333067803253.JavaMail.root@mail.absfoc.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On 3/29/12 6:36 PM, Brian R. Watters wrote:
> We are about to accept a 20MEG Ethernet feed via Comcast and their
> fiber plant as well as a BGP feed across the same link.
>
> I have a space GIGE interface on a 7206VXR and would like to know
> best practice for deploying for optimal performance across this
> interface.
>
> Any ideas and or direction would be extremely helpful as we are
> seeing some real issues such as.
>
> Direct connect (without BGP) to the CPE from Comcast (Fiber to
> Ethernet) via a laptop gives the level of performance we would
> expect, However as soon as we terminate to our router via the GIGE
> which is set to 100MB full duplex and all flow control turned off
> (Negotiation auto) per Comcast and connect up via a 100MB fast
> Ethernet interface directly connected we get a fraction of the speed
> when direct connected.
From my own experience here with our 7200s, some of the PA based
100BaseT interfaces (ie: not on the IO module) can not negotiate
100-full, but rather only half. This leaves one end diff then the other
and creates issues with performance. Try forcing both the laptop and
router to 100-full and see if it helps.
--
Brielle Bruns
The Summit Open Source Development Group
http://www.sosdg.org / http://www.ahbl.org
