FRTS strange, plz help !

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Jun 1st, 2008
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hi all, i took this example from wendell odom exam cert

map-class frame-relay shape-all-64

frame-relay traffic-shape 64000

now it was written in description that bc was calculation using bc = tc * cir where tc defaults to 125 ms, in which case bc should be 8000, but in the result of show traffic-shape, under "sustain bits/int" the value is 64000 !!! why is this so ? i have checked on a real router and its also giving me the same value, dont u think its strange ??

kindly tell me wat i am missing here

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slmansfield Sun, 06/01/2008 - 17:21
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The 64kbps is the shaping rate. 8kbps is the Bc. With a Tc of 125ms, there are eight intervals per second, which comes out to 8kbps per interval x 8 intervals or 64kbps.

illusion_rox Sun, 06/01/2008 - 18:36
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hi slman, but in normal CB shaping, if i only define shape average 64000, then under "sustain bits/int" showed 8000, now as the heading suggest sustain bits per "interval" then i think i should show 8000, why is it showing 64000 ?

ashok_boin Sun, 06/01/2008 - 22:31
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I am afraid to see "frame-relay traffic-shape" command under map-class configuration. There is no specific command like this. Which exact command did you issue? Can you please give the configuration and "sh traffic-shape" command outputs.



slmansfield Mon, 06/02/2008 - 06:59
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There are some errors in the certification documentation. I think the command should be:

frame-relay traffic-rate 64000 64000

There is no such command as:

frame-relay traffic-shape

slmansfield Mon, 06/02/2008 - 07:19
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You could shape from within a map-class, which would give you the Bc=8kbps with a Tc of 125ms (the default in this case). This method provides more flexibility in tuning the shaping parameters.

map-class frame-relay SHAPE_ALL

frame-relay cir 64000

frame-relay bc 8000

interface serial0/0

frame-class SHAPE_ALL

frame-relay traffic-shaping

illusion_rox Tue, 06/03/2008 - 00:06
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hi all, sorry for mistyping, the command was surely frame-relay traffic-rate 64000 64000 and here is the output

R1#sh traffic-shape

Interface Se0/0

Access Target Byte Sustain Excess Interval Increment Adapt

VC List Rate Limit bits/int bits/int (ms) (bytes) Active

102 64000 1000 64000 0 125 1000 -

(i think its not properly alligned but still) kindly see under sustain bits its giving 64000 !! why ? plz i am not looking for alternate solutions, i know how to do it from normal CB shaping, all i am looking for is the meaning of why its 64000 written under sustain bits ??? why it isnt 8000 ?

see if i use normal CB shaping using this config

policy-map shape-all

class class-default

shape average 64000

int se 0/0

service-policy output shape-all

now if i issue command

show policy-map int se 0/0

then under sustain bits its written 8000 !!!! all other values are same, so i am asking why in FRTS its showing me 64000 ? where it should be 8000 dont u guys think ?, i mean no disrespect to any1 i am very thankful to those who replied but i am not looking for a alternate solution, i want to know why the output is showing 64000 and not 8000 ?

Kindly guide me in this


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