From: Ian.C.Stong@xxxxxxxxxxxxxxx
Date: Thu Jun 20 2002 - 15:48:06 GMT-3
I've also seen reference to the CIR as follows:
sampling rate = bc/CIR so CIR = bc/sampling rate.
So a bc of 64k and a sampling rate of 125ms would equate to a CIR of X.
-----Original Message-----
From: anthonypace [mailto:anthonypace@fastmail.fm]
Sent: Thursday, June 20, 2002 12:35 PM
To: kyeung; mamoor
Cc: Thai.Nguyen; kurt; m.popovich; ccielab
Subject: Re: FRTS
I also keep seeing this reference to setting the CIR to the port speed
in all the CCO an in all the books and in these posts. I guess I will
adhere to this in the lab since I am seeing that this CCIE effort is
more theory than practical, however, what I have observed in real life
is that traffic shaping is used when many, many logical circuits
inhabit a phisical link (ATM or FRAME). In the case of frame-relay, if
the hub has 1544 kbps and 8 pvc's with 8 class's and each spoke has 64k
on each of their circuits,how can the CIR be 1544 on every map class.
Isn't the idea to carve up the bandwidth amongst the spokes?
Anthony Pace
On Thu, 20 Jun 2002 22:31:25 +0800 (HKT), "Katson Yeung"
<kyeung@mail.hkcix.com> said:
> Thanks Mamoor, that is correct.
>
> One more question about the CIR.
>
> According to all the materials I read, the recommended value for CIR
is
> set it to Access-rate. So, there is a question:
>
> R1s0 ------ FR -------- s0R2
>
> R1s0 = 1.544Mbps
> R2s0 = 128kbps
> CIR = 64k. (I know it is = mincir, irrelevent to the question, but
list
> it
> out anyway.)
>
>
> At R1,
> should I set the CIR as 1544000 or 128000?
>
> I strongly think that it is no point to set it as 1544000 since the
> port
> speed at another side is 128000, there is no way that it R2 can receve
> data in that rate.
>
>
>
> On Wed, 19 Jun 2002, Ahmed Mamoor Amimi wrote:
>
> > minCIR = Guranteed rate that provider promised
> > CIR = AR
> > and AR = Access-Rate . This is the rate of transmit and recieve of
the
> > interface.
> >
> > Like for example provider agree to give u a min of 64k, but ur
interface can
> > support upto 1.54Mb.
> > U have to negotiate with the provider that how much i can burst
above my
> > minCIR. The bursting
> > totally depends upon the AR or CIR. The more the AR the more u can
burst.
> > (but depend upon
> > the provider that allow u bursting).
> >
> > Hope i have cleared my point.
> >
> > -Mamoor
> >
> >
> >
> > ----- Original Message -----
> > From: Nguyen, Thai <Thai.Nguyen@auspost.com.au>
> > To: 'Erhan Kurt' <kurt@superonline.net>; Katson PN Yeung
<kyeung@hkcix.com>;
> > Michael Popovich <m.popovich@mchsi.com>; CCIE GROUPSTUDY
> > <ccielab@groupstudy.com>
> > Sent: Thursday, June 20, 2002 5:00 AM
> > Subject: RE: FRTS
> >
> >
> > > Hi,
> > >
> > > I am having difficulty in understanding the difference between
minCIR and
> > > CIR.
> > > Typically minCIR is the guarantee from the service provider, so
how and
> > what
> > > would we use to determine the CIR. Can someone shed some light.
> > >
> > > Thank in advance.
> > >
> > > -----Original Message-----
> > > From: Erhan Kurt [mailto:kurt@superonline.net]
> > > Sent: Tuesday, June 11, 2002 5:38 PM
> > > To: Katson PN Yeung; Michael Popovich; CCIE GROUPSTUDY
> > > Subject: RE: FRTS
> > >
> > >
> > > For example, in voice, Tc=125 msec may cause pain :)
> > >
> > >
> > > Never Ever Give Up,
> > > Erhan
> > >
> > >
> > > -----Original Message-----
> > > From: Katson PN Yeung [mailto:kyeung@hkcix.com]
> > > Sent: 11 Haziran 2002 Sal} 10:39
> > > To: Erhan Kurt; Michael Popovich; CCIE GROUPSTUDY
> > > Subject: RE: FRTS
> > >
> > >
> > > A minor correction about "frame-relay traffic-rate" commend in the
> > > map-class frame-relay.
> > >
> > > After you specified traffic-rate, everything displayed will be in
> > > bit-per-second, but internally all other values, such as Bc, Be,
CIR,
> > > mincir are still be calculated in tc=125ms.
> > >
> > >
> > > At 03:00 PM 6/11/2002, Erhan Kurt wrote:
> > > >Tc=Bc/CIR
> > > >
> > > >Look at output of time interval as an important thing in QoS..
With
> > > >traffic-rate, you cannot specify any Tc (default=125 msec).
> > > >
> > > >
> > > >-----Original Message-----
> > > >From: Michael Popovich [mailto:m.popovich@mchsi.com]
> > > >Sent: 09 Haziran 2002 Pazar 23:49
> > > >To: CCIE GROUPSTUDY
> > > >Subject: FRTS
> > > >
> > > >
> > > >What is the difference between this:
> > > >
> > > >map-class frame-relay p2p
> > > > frame-relay cir 400000
> > > > frame-relay bc 8000
> > > > no frame-relay adaptive-shaping
> > > >
> > > >Interface Se0/0.1
> > > > Access Target Byte Sustain Excess Interval
Increment
> > > Adapt
> > > >VC List Rate Limit bits/int bits/int (ms)
(bytes)
> > > >Active
> > > >104 400000 1000 8000 0 20 1000
-
> > > >
> > > >and this:
> > > >
> > > >map-class frame-relay p2p
> > > > frame-relay traffic-rate 400000 408000
> > > > no frame-relay adaptive-shaping
> > > >
> > > >Interface Se0/0.1
> > > > Access Target Byte Sustain Excess Interval
Increment
> > > Adapt
> > > >VC List Rate Limit bits/int bits/int (ms)
(bytes)
> > > >Active
> > > >104 400000 7250 400000 8000 125 6250
-
> > > >
> > > >
> > > >
> > > >I see some differences in the output but could someone explain
the
> > > >functional differences here and what impact it would have.
> > > >
> > > >I have been looking at some lab questions that require setting up
> > > >traffic shaping and give you a cir and a bir value. The solution
used
> > > >the frame-relay traffic-rate under the map-class where as I was
looking
> > > >towards setting the CIR and the Bc values. I am a little confused
on
> > > >the BIR value.
> > > >
> > > >TIA
> > > >
> > > >MP
This archive was generated by hypermail 2.1.4 : Tue Jul 02 2002 - 08:12:39 GMT-3