From: ccie2be (ccie2be@nyc.rr.com)
Date: Sun Nov 21 2004 - 19:35:30 GMT-3
Hi Bob,
As I going over all the old GS posts on policing, I came this one comparing
CAR and Police.
According to the DQoS by Odem, one of the differences is that with CAR you
can configure nested rate-limit commands but not with MQC. Since there's
been alot of new features added to MQC, I wonder if that still holds true.
For example, according to Odem, you couldn't enable MQC on a per dlci basis,
but since now you can match on dlci, you can.
So, I wonder if a config like this would fly
policy-map VOICE
class VOICE
police 128000
policy-map ALL-TRAFFIC
class class-default
police 256000
service-policy VOICE
Any thoughts?
Thanks, Tim
----- Original Message -----
From: "Bob Sinclair" <bsin@cox.net>
To: "Anas Tarsha" <ra3i@yahoo.com>;"Group Study" <ccielab@groupstudy.com>
Sent: Saturday, December 06, 2003 9:51 PM
Subject: Re: CAR vs Police
> Anas,
>
> I would agree that Cisco could do a better job of explaining the policing
> mechanism in the MQC, but I think I would disagree that it permits
buffering
> during congestion. There are Bc and Be parameters, but according to the
> documentation this does not buffer packets to shape the traffic. The best
> explanation I have found is at the link below, which says that the policer
> does not buffer, but "drops packets less aggressively" during congestion.
> Could you check it out and see what you think of it?
>
>
http://www.cisco.com/en/US/partner/tech/tk543/tk545/technologies_q_and_a_item09186a00800cdfab.shtml#Q24
>
> Thanks!
>
> -Bob Sinclair
> CCIE #10427, CISSP, MCSE
>
>
> bsinclair@netmasterclass.net
> ----- Original Message -----
> From: "Anas Tarsha" <ra3i@yahoo.com>
> To: "Bob Sinclair" <bsin@cox.net>; "ccie2be" <ccie2be@nyc.rr.com>; "Group
> Study" <ccielab@groupstudy.com>
> Sent: Saturday, December 06, 2003 9:07 PM
> Subject: Re: CAR vs Police
>
>
> > Also theoretically there is a major difference between
> > CAR and policing, a difference which Cisco hardly
> > explains it well in my opinion. CAR is a rate-limit
> > mechanism to limit the input or output transmission
> > rate on an interface or subinterface based on a
> > configured value. All the exceeding traffic is dropped
> > in case the exceeding action is dropping. Policing is
> > more like a shaping mechanism. As the name implies,
> > shaping does not drop packets in case of congestion,
> > it buffers them. You will see delay but no data loss.
> > So this is the major difference, CAR does not buffer.
> >
> > Anas
This archive was generated by hypermail 2.1.4 : Thu Dec 02 2004 - 06:57:48 GMT-3