From: Andy (and123and@googlemail.com)
Date: Wed May 23 2007 - 07:51:22 ART
Thanks Edison, still dont get it tho :-(
AR = 384000
CIR = 192000
Bc = 24000
Be = 24000
Configure as :
frame-relay CIR 192000
frame-relay bc 24000
frame-relay mincir 128000
frame-relay be 24000
Gives us the following:
Tc1 : (Bc 24000 + Be 24000)
Tc2 : (Bc 24000 + Be 24000)
Tc3 : (Bc 24000 + Be 24000)
Tc4 : (Bc 24000 + Be 24000)
Tc5 : (Bc 24000 + Be 24000)
Tc6 : (Bc 24000 + Be 24000)
Tc7 : (Bc 24000 + Be 24000)
Tc8 : (Bc 24000 + Be 24000)
but, if we can only send Be during first interval (
http://www.cisco.com/warp/customer/125/traffic_shaping_6151.html
"The amount of excess data allowed to be sent during first Tc interval in
bits "), then this would mean
Tc1 : (Bc 24000 + Be 24000) = ok
Tc2 : (Bc 24000 + Be 24000) = only Bc sent as Be sent ONLY during Tc1
Tc3 : (Bc 24000 + Be 24000) = only Bc sent as Be sent ONLY during Tc1
Tc4 : (Bc 24000 + Be 24000) = only Bc sent as Be sent ONLY during Tc1
Tc5 : (Bc 24000 + Be 24000) = only Bc sent as Be sent ONLY during Tc1
Tc6 : (Bc 24000 + Be 24000) = only Bc sent as Be sent ONLY during Tc1
Tc7 : (Bc 24000 + Be 24000) = only Bc sent as Be sent ONLY during Tc1
Tc8 : (Bc 24000 + Be 24000) = only Bc sent as Be sent ONLY during Tc1
Giving us (Bc 24000 x 8) + (Be 24000 from Tc1) = 216000 AR !
Therefore should we not configure Be as 192000 to give us
Tc1 : (Bc 24000 + Be 192000) = ok
Tc2 : (Bc 24000 + Be 192000) = only Bc sent as Be sent ONLY during Tc1
Tc3 : (Bc 24000 + Be 192000) = only Bc sent as Be sent ONLY during Tc1
Tc4 : (Bc 24000 + Be 192000) = only Bc sent as Be sent ONLY during Tc1
Tc5 : (Bc 24000 + Be 192000) = only Bc sent as Be sent ONLY during Tc1
Tc6 : (Bc 24000 + Be 192000) = only Bc sent as Be sent ONLY during Tc1
Tc7 : (Bc 24000 + Be 192000) = only Bc sent as Be sent ONLY during Tc1
Tc8 : (Bc 24000 + Be 192000) = only Bc sent as Be sent ONLY during Tc1
Can someone explain (or unexplain :-) the above, I understand all the maths,
just this first time interval Tc1 is getting me.
-A
On 22/05/07, Edison Ortiz <edisonmortiz@gmail.com> wrote:
>
> Andy,
>
> You are sending 24kilobits per TC which is 125ms or 1/8 of a second.
>
> The CIR is set to 192 kilobits per *second*.
>
> Multiply 24 * 8 and you will get what you are sending per second which is
> 192
>
> HTH,
>
>
> __
>
> Edison Ortiz
> (Routing & Switching, CCIE # 17943)
>
>
>
>
> ----- Original Message -----
> *From:* Andy <and123and@googlemail.com>
> *To:* Edison Ortiz <edisonmortiz@gmail.com>
> *Cc:* Group Study (E-mail) <ccielab@groupstudy.com>
> *Sent:* Tuesday, May 22, 2007 10:43 AM
> *Subject:* Re: FRTS and Be - first interval?
>
>
> Quote
> > Why is Be 24000 and not 192000, if the definition of Be is "The number
> of
> > non-committed bits the router is allowed to send above Bc during the *
> first
> *> interval Tc"
> /Quote
>
> The bit that confuses me, is that it says it sends during the first
> interval Tc. This suggests (given default Tc)
>
> Tc1 Tc2 Tc3 Tc4 Tc5 Tc6 Tc7 Tc8
>
> (Bc + Be) (Bc) (Bc) (Bc) (Bc) (Bc) (Bc) (Bc)
>
> Therefore I would config Be at 192000, so as to reach AR.
> If we configure Be at 24000, and given that Be only sends during first Tc,
> we are only getting Bc (192000) + Be for Tc1 (24000) which does not equal
> Ar.
>
> I understand the maths and how to acheive the figures, what I dont get is
> why do we configure Be for each Tc "Tc1 - Tc8" when it says Be is only sent
> during *first *Tc (Tc1).
> -A
>
>
> *************************************************************
>
>
> On 22/05/07, Edison Ortiz <edisonmortiz@gmail.com> wrote:
> >
> > Quote
> > > Why is Be 24000 and not 192000, if the definition of Be is "The number
> > of
> > > non-committed bits the router is allowed to send above Bc during the
> > first
> > > interval Tc"
> > /Quote
> >
> > You have to use the same Tc value for the Be that was used for the Bc.
> > As you stated originally, "use the default Tc value" which is 125ms.
> >
> > So they gave you the Access Rate, CIR and MinCIR.
> >
> > You take the CIR 192000 and multiply it for .125 which gives you the Bc
> > (24000)
> > You have another 192kbps for bursting (384000 - 192000) so you take that
> > amount
> > and do the same calculation (192000 * .125) to get the Be (24000)
> >
> >
> >
> >
> > __
> >
> > Edison Ortiz
> > (Routing & Switching, CCIE # 17943)
> >
> >
> >
> > ----- Original Message -----
> > From: "Andy" <and123and@googlemail.com >
> > To: "Group Study (E-mail)" <ccielab@groupstudy.com>
> > Sent: Tuesday, May 22, 2007 5:42 AM
> > Subject: FRTS and Be - first interval?
> >
> >
> > > http://www.internetworkexpert.com/resources/01700368.htm
> > > Slide 31 Example 2
> > >
> > > The example in above URL shows:
> > > Router has AR of 384000
> > > CIR of 192000
> > > MinCIR 128000
> > > Use default Tc and allow to burst up to AR.
> > >
> > > The configuration shows:
> > > frame-relay CIR 192000
> > > frame-relay bc 24000
> > > frame-relay mincir 128000
> > > frame-relay be 24000
> > >
> > > Why is Be 24000 and not 192000, if the definition of Be is "The number
> > of
> > > non-committed bits the router is allowed to send above Bc during the
> > first
> > > interval Tc"
> > >
> > > Confused :-/
> > >
> > >
> > _______________________________________________________________________
> > > Subscription information may be found at:
> > > http://www.groupstudy.com/list/CCIELab.html
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