Re: use of CS in qos?

I know what you mean, I would bet it's just the DSCP terminology.

On Fri, Jul 3, 2009 at 4:18 PM, abderrahim sadki <a_sadki1_at_hotmail.com>wrote:

> thanks for your answer.
>
> but i was wondering does a device (understading only IPP) gets a DSCP
> marking
> isnt it going to ignore the last 3 bits anyway?
> if yes what the point of the CS?
>
> Abderrahim
>
> Date: Fri, 3 Jul 2009 18:12:33 -0400
> Subject: Re: use of CS in qos?
> From: jastorino_at_ipexpert.com
> To: a_sadki1_at_hotmail.com
> CC: ccielab_at_groupstudy.com
>
> Hey,
>
> IPP uses the most significant 3 bits in the ToS field in the IP header.
> With
> DSCP the CS values essentially do the same thing. In order to be backwards
> compatible with IPP it only uses the 3 most significant bits. Maybe this
> will help you visualize:
>
>
> CSx Dec. IPP Binary
>
> CS1 8 1 001 000
> CS2 16 2 010 000
> CS3 24 3 011 000
> CS4 32 4 100 000
> CS5 40 5 101 000
> CS6 48 6 110 000
> CS7 56 7 111 000
>
> HTH
>
>
> On Fri, Jul 3, 2009 at 5:04 PM, abderrahim sadki <a_sadki1_at_hotmail.com>
> wrote:
>
> Hi all.
>
> I understand that CS is used for backward compatibility with IP precedence.
>
> My question is :
>
> if a device only understands the IP precedence and it receives a packet
> with
> the dscp marking isnt it going to ignore the last 3 bits anyway?
>
> Thanks,
> Abderrahim
>
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