From: NET HE (he_net@hotmail.com)
Date: Tue Jan 20 2009 - 23:32:08 ARST
Maybe my understanding is wrong.
Firstly, let's consider this case, for a speed 100M interface, there are only
71M bits of traffic, the utilization of the interface is 71%, but surely there
is no congestion.
Secondly, speaking of burst, I think I can set any burst rate as I want as
long as the device has enough software buffer. And between the interface and
software buffer, there is a hardware buffer to smooth the traffic to interface
line speed.
Thirdly, the command "frame-relay congestion threshold" is for frame-relay
switch.Best Regards, Net (Xin) He
Date: Tue, 20 Jan 2009 13:59:00 +0100Subject: Re: Policing or ShapingFrom:
slidersv@gmail.comTo: he_net@hotmail.comCC: ccie.tobe81@gmail.com;
sadiqtanko@gmail.com; ccielab@groupstudy.comUh... Net He,that's not how
interfaces work.You cannot send at any other speed then the interface speed.
Interface can have either on or off state - don't forget that it's
digital.Check out chapter on test setup in the following document to
understand the need for queueing:
http://www.boxoid.org/cisco/MAX-RESERVED-BANDWIDTH-AND-CBWFQ.pdf75%
utilization is counted using packets over time and with such high utilization,
there is 99% chance that router is queuing like crazy. The only scenario this
would not be true is if you had shapers in the path before or if you'd use
real time operating systems.Raul: Policing can mark/remark packets that exceed
rate, so policing with "set-de-transmit" as exceed action could work for you.
But to tell the other router what to do... um... You could write a complecated
EEM script. Or maybe just use something like "frame-relay congestion threshold
de 75"? Can you use foresight messages?Telling othber routers what to do
without FECN/BECN could be complicated. You could tell end-hosts what to do,
by dropping packets...
On Tue, Jan 20, 2009 at 3:12 AM, NET HE <he_net@hotmail.com> wrote:
Since the condition is 70% utilization of bandwidth, in other words, there is
no congestion. So congestion management of using queues can't be used. And
congestion avoidance works on queues instead of bandwidth utilization, so
congestion avoidance is not an option either. Traffic shaping can't set bits
to inform other network nodes, so it is excluded. Traffic policing can set
bits based on bandwidth utilization, but the bits are to inform downstream
network instead of upstream network. Best Regards, Net (Xin) He > Date: Mon,
19 Jan 2009 19:32:16 +0400> Subject: Re: Policing or Shaping> From:
ccie.tobe81@gmail.com> To: sadiqtanko@gmail.com> CC: slidersv@gmail.com;
ccielab@groupstudy.com
> > Hi,> > Local router needs to inform remote router that network is
congested and> remote router needs to slow down packet forwarding once traffic
utilization> on FR interface of local router will reach 75%. Don't use FECN or
BECN.> > > HTH> > On Mon, Jan 19, 2009 at 7:16 PM, Sadiq Yakasai
<sadiqtanko@gmail.com> wrote:> > > Well, cos of "and we need to inform remote
router that there is congestion> > in network.", I would tend to think we need
to inform the remote router that> > there is congestion on the network, so
that an immediate action would be> > taken.> >> > I think there isnt enough
information from the question to provide an> > exactly solution.> >> >
Anyways, just my 2 cents.> >> > Sadiq> >
> Blogs and organic groups at http://www.ccie.net> >
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