[AusNOG] DSCP on internet services

[Balmik Soin]

Have seen this behaviour on Cisco routers before, traced it back to it being picky about which traffic types it will re-mark - for instance in this case, it wouldn't re-mark DSCP for IPSec traffic when it was being matched in the class-default catchall.

Assume this is some sort of "feature" in the IOS release being used on the router at the time :)

- Balmik.


-----Original Message-----
From: ausnog-bounces at lists.ausnog.net [mailto:ausnog-bounces at lists.ausnog.net] On Behalf Of Craig Meyers
Sent: Wednesday, 17 February 2010 3:47 PM
To: ausnog at ausnog.net
Subject: Re: [AusNOG] DSCP on internet services


FYI

Today as an example, on our netflow stats we receive 1-2% traffic marked with something other than zero.

So the odd non-zero flow gets through.

-- Craig Meyers

-----Original Message-----
From: ausnog-bounces at lists.ausnog.net [mailto:ausnog-bounces at lists.ausnog.net] On Behalf Of McDonald Richards
Sent: Wednesday, 17 February 2010 4:09 PM
To: ausnog at ausnog.net
Subject: Re: [AusNOG] DSCP on internet services

Yeah - the Internet ones ;)

Macca


From: Phillip Grasso [mailto:phillip.grasso at gmail.com]
Sent: Wednesday, 17 February 2010 5:00 PM
To: McDonald Richards
Cc: Raymond, Adam; ausnog at ausnog.net
Subject: Re: [AusNOG] DSCP on internet services

I'm assuming your resetting dscp to 0 from your customers as well?


On Wed, Feb 17, 2010 at 4:28 PM, McDonald Richards <macca at vocus.com.au>
wrote:
Agreed. Standard practice at every place I've worked has been to remark DSCP to 0 on ingress for all "Internet" traffic.

Macca


From: ausnog-bounces at lists.ausnog.net
[mailto:ausnog-bounces at lists.ausnog.net] On Behalf Of Phillip Grasso
Sent: Wednesday, 17 February 2010 4:17 PM
To: Raymond, Adam
Cc: ausnog at ausnog.net
Subject: Re: [AusNOG] DSCP on internet services

sorry let me be clear,
resetting dscp bits to 0 (or other internal classify for best effort) is normal for large ISP's with internal qos policies. proper behaviour is to leave last two bits alone for ECN, but I doubt ecn bits are passed across the internet freely.
On Wed, Feb 17, 2010 at 3:56 PM, Phillip Grasso <phillip.grasso at gmail.com>
wrote:
My understanding that is the de facto standard for most large SP's .
Especially if they run their own qos policies internally.

On Wed, Feb 17, 2010 at 3:42 PM, Raymond, Adam <Adam.Raymond at nn.com.au>
wrote:
All,

            I am wandering if other networks modify the DSCP of internet customers when they receive the traffic from the customer (such as resetting it to BE for all traffic). What is seen as being "best practice" for this operation.

Regards,

Adam Raymond

IP Project Engineer
NextGen Networks
www.nextgennetworks.com.au
Direct:   03 8623 3638
Level 6, 333 Collins St
Melbourne  VIC  3000

_______________________________________________
AusNOG mailing list
AusNOG at lists.ausnog.net
http://lists.ausnog.net/mailman/listinfo/ausnog