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RE: Custom Queue Confusion posted 06/01/2003
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Ratios work just like fractions. Look for the lowest common denominator.


It is easy to see that 2/4 is the same as 1/2. Thus 25/15 = 5/3. 

He just noticed that the numbers in the original ratios all ended in 0
or 5, which (as you have pointed out) means they are divisible by 5.


> -----Original Message-----
> From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On 
> Behalf Of Jason Cash
> Sent: Sunday, June 01, 2003 1:22 PM
> To: 'Nguyen Hoang Long'; ccielab@xxxxxxxxxxxxxx
> Subject: RE: Custom Queue Confusion
> 
> 
> That actually is the correct answer, but how did you come to get:
> 
> 30:30:25:15 =  6:6:5:3 ?
> 
> How did you know to divide by 5 to get 6:6:5:3?  Or did you 
> use some other
> calculation?
> 
> -----Original Message-----
> From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On 
> Behalf Of
> Nguyen Hoang Long
> Sent: Sunday, June 01, 2003 2:54 AM
> To: Jason Cash; ccielab@xxxxxxxxxxxxxx
> 
> Hi Jason,
> 
> I would do by this way for exact ratio:
> 
> IP:SNA:IPX:telnet  =  30:30:25:15 =  6:6:5:3
> 
> therefore:
> 
>     IP = 1500x6 = 9000  (30%)
> 
>     SNA = 1500x6 = 9000  (30%)
> 
>     IPX = 1500x5 = 7500  (25%)
> 
>     Telnet = 1500x3 = 4500 (15%)
> 
> Since we're using new IOS, which permits the router to borrow 
> from the next
> queue for a current queue,  your calculation method is not 
> necessary. I
> prefer a more simple method.
> 
> Long
> ----- Original Message ----- 
> From: "Jason Cash" <cash2001@xxxxxxxxxx>
> To: <ccielab@xxxxxxxxxxxxxx>
> Sent: Sunday, June 01, 2003 12:28 PM
> Subject: Custom Queue Confusion
> 
> 
> > I am getting really confused on the custom queuing!  I have 
> looked over
> the
> > previously provided links, but those examples don't address 
> the problem I
> am
> > having.  Whereas I am instructed:
> >
> >
> >
> > IP traffic 30% bw
> >
> > SNA traffic 30% bw
> >
> > IPX traffic 25% bw
> >
> > Telnet traffic 15% bw
> >
> >
> >
> > Here is what I do (average pkt 1500)
> >
> > 1) For each queue, divide the percentage of bandwidth you 
> want to allocate
> > to the queue by the packet size, in bytes.
> >
> > 30/1500 = .02
> >
> > 30/1500 = .02
> >
> > 25/1500 = .0166
> >
> > 15/1500 = .01
> >
> >
> >
> > 2) Normalize the numbers by dividing by the lowest number:
> >
> > .02/.01 = 2
> >
> > .02/.01 = 2
> >
> > .0166/.01 = 1.66
> >
> > .01/.01 = 1
> >
> >
> >
> > 3) A fraction in any of the ratio values means that an 
> additional packet
> > will be sent. Round up the numbers to the next whole number 
> to obtain the
> > actual packet count.
> >
> > IP = 2
> >
> > SNA = 2
> >
> > IPX = 2
> >
> > Telnet = 1
> >
> >
> >
> > 4) Convert the packet number ratio into byte counts by 
> multiplying each
> > packet count by the corresponding packet size.
> >
> > IP = 1500x2 = 3000
> >
> > SNA = 1500x2 = 3000
> >
> > IPX = 1500x2 = 3000
> >
> > Telnet = 1500x1 = 1500
> >
> >
> >
> > Now here is one place I get lost.  IPX byte count is the 
> same as IP and
> SNA
> > and I know that can't be right, but what do I do?  2 is the 
> only multiple
> to
> > go by.
> >
> >
> >
> > 5) To determine the bandwidth distribution this ratio 
> represents, first
> > determine the total number of bytes sent after all three queues are
> > serviced:
> >
> > Based on my info above I get: 3000+3000+3000+1500= 10500
> >
> >
> >
> > 6) Then determine the percentage of the total number of 
> bytes sent from
> each
> > queue:
> >
> > IP = 3000/10500 = .28 (28%)
> >
> > SNA = 3000/10500 = .28 (28%)
> >
> > IPX = 3000/10500 = .28 (28%)
> >
> > Telnet = 1500/10500= .14 (14%)
> >
> >
> >
> > This adds up to 98%.  So I will wait for some advice before 
> I proceed.
> > Basically, when I a queue is rounded up and is equal to a 
> greater queue,
> how
> > is that queues byte count determined?