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RE: custom queueing byte-count question posted 09/29/2001
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In this case, if packet size for dlsw is 512 bytes, 256 for ip, and 1024 for ipx....How can I make this 
custom queue exact match bandwidth.  Shall I change the serial interface's mtu to 1024 ?


Liekun Ye

The guideline that I follow is to look at the MTU.  You will never see a
packet larger than the MTU for that interface.

Typically, we are queueing on a serial line which has a MTU of 1500 bytes.
Therefore we use a baseline queue byte count of 1500 bytes.  If we were
using a token Ring interface we would want to change the baseline queue byte
count to 8136 bytes or whatever the MTU is set to.  

Serial or ethernet
Since 25% is the lowest percentage, it gets the baseline bytecount
queue 1: 25%=1500 bytes
queue 2: 50%=2*25%=2*1500=3000 bytes
queue 3: 25%=baseline=1500 bytes

Token Ring
Since 25% is the lowest percentage, it gets the baseline bytecount
queue 1: 25%=8136 bytes
queue 2: 50%=2*8136=16272 bytes
queue 3: 25%=baseline=8136 bytes

The bandwidth that a custom queue is equal to 
(queue byte count / total byte count of all queues) * bandwidth capacity of
the interface

For example a T-1
q1: (1500/6000)*1.544=.25*1.544=.386
q2: (3000/6000)*1.544=.5*1.544=.772
q3: (1500/6000)*1.544=.25*1.544=.386

I hope this helps.
Earl Aboytes, CCIE 6097
-----Original Message-----
From: Raji Mohan
To: ccielab@xxxxxxxxxxxxxx
Sent: 9/28/2001 7:34 PM
Subject: custom queueing byte-count question

I've never been able to calculate the byte-count specified correctly. Is
there a good reference to learn this? For eg. if it is told to assign
of the frame-relay intf bw to dlsw, 25% to ip and 25% to ipx.. how does
one go about allocating byte-count for a custom queue. Any help would be

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