Thanks for the details debugs Jeff.
Just wanted to double check with you that my examples are also correct ?
Thanks again
Shrini
On 1/5/2011 2:42 PM, Roig Borrell, Francesc Xavier wrote:
Hi guys,
Yes, thinking twice it doesn’t make a lot of sense consider the call
with the worst case payload (46.4) in order to adding RSVP signaling.
1 RSVP Request
Dec 17 18:47:58.630: RSVP
10.10.110.2_16548->10.10.110.1_17938[0.0.0.0]: start requesting 40
kbps FF reservation for 10.10.110.2
2 RSVP update (Call established )
Dec 17 18:49:10.047: RSVP-RESV: Locally created reservation. No
admission/traffic control needed
Dec 17 18:49:10.047: RSVP
10.10.110.2_16510->10.10.110.1_19416[0.0.0.0]: start requesting 24
kbps FF reservation for 10.10.110.2
In fact in the first step, there isn’t RTP traffic, so in case of
congestion the PQ only will have some RSVP packets.
So the requirement can be achieved PQ = 27,2*2 + X, X (extra RSVP
signaling traffic, as Miron we can consider 1kbps)
Now, I believe we all agree!! J
Thanks for your help! Happy studies!
Francesc
*De:*givemeccievoice2...@gmail.com [mailto:givemeccievoice2...@gmail.com]
*Enviado el:* miércoles, 05 de enero de 2011 22:42
*Para:* 'Miron Kobelski'
*CC:* Roig Borrell, Francesc Xavier; 'Shrini';
ccie_voice@onlinestudylist.com
*Asunto:* RE: [OSL | CCIE_Voice] RSVP LLQ priority value calculation
After I just agreed with you! J
Below is not the RSVP calculation. That is the LLQ bandwidth
calculations. After I reviewed my notes and figured out the value
necessary, I referred to the PG. The PG calculates the PQ bandwidth
by using 1 call at 10ms and 1 call at 20ms. I am confused as to why
they do it this way. I would think that you would use the 27.2 Kbps
for each call and arrive at a 55 Kbps BW in the LLQ. I agree with you
that the RSVP communications will only require minimal overhead and
you can just simply add a couple of Kbps to accomplish this task.
Remember, the question that Francesc was referring to assumes you have
RSVP configured already, and is asking you to configure the LLQ
including the necessary overhead for RSVP messages.
Jeff
*From:*Miron Kobelski [mailto:findko...@gmail.com]
*Sent:* Wednesday, January 05, 2011 1:13 PM
*To:* givemeccievoice2...@gmail.com
*Cc:* Roig Borrell, Francesc Xavier; Shrini;
ccie_voice@onlinestudylist.com
*Subject:* Re: [OSL | CCIE_Voice] RSVP LLQ priority value calculation
I disagree... I would never include L2 in RSVP bandwidth calculations.
To see what values RSVP uses, check "show ip rsvp installed" in
ringing and connected states. it is 40 and 24 kbps for g729.
I'd say that RSVP overhead should constitute no more then 1kbps (only
several small messages during RSVP negotations!)
regards
kobel
On Wed, Jan 5, 2011 at 20:53, <givemeccievoice2...@gmail.com
<mailto:givemeccievoice2...@gmail.com>> wrote:
FRF.12 – 8
40 + 20 + 8 = 68
68 bytes * 8 bits = 544 bits per packet
544 bpp * 50 pps = 272000 bps or 27.2 Kbps
2 G729 calls * 27.2 Kbps = 54.4 Kbps or roughly 55 Kbps
A basic LLQ without RSVP overhead would need to have a priority 55
command. However, the question asks for you to take this extra
overhead for RSVP into account.
IP/UDP/RTP - 40
Payload – 10
FRF.12 – 8
40 + 10 + 8 = 58 bytes
58 * 8 = 464 bpp
464 * 100 pps = 46400 bps or 46.4 Kbps
Therefore the bandwidth calculation would instead be 27.2 + 46.4 =
73.6 Kbps or 74 Kbps.
Hope this helps,
Jeff
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