# how do I set the time interval for FRTS?

Answered Question

I need to set FRTS with a cir of 128k but I need to lower the time interval to the minimum, I think is 150ms, any help plese?

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Correct Answer by jbrenesj about 7 years 8 months ago

10ms is the smallest interval. the default is 150ms.

Bc = Tc * cir

Just don't use the command for tc under the map-class because that's not the way to set a specific interval.

Use the formula and then configure the cir and the Bc

Overall Rating: 5 (4 ratings)

## Replies

Edison Ortiz Tue, 08/18/2009 - 17:18
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The lowest time interval is 10ms and you can achieve it with the following formula:

Tc = Bc / CIR

map-class frame-relay FRTS

frame-relay cir 128000

frame-relay bc 1280

This will provide a 10ms Tc.

HTH,

__

Edison.

Jerry Ye Tue, 08/18/2009 - 17:19
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Hi Joseph,

The lowest Tc is 10ms. When you are configuring map-class for FRTS, the router will calculate Tc when you configured the CIR and Bc. You can use this formular to calculate Bc

CIR = Bc / Tc , where Tc is in second

Tc = 10/1000 = 0.01

128000 = Bc / 0.01

Bc = 128000 x 0.01 = 1280

map-class frame-relay FRTS

frame-relay cir 128000

frame-relay bc 1280

interface Serial0/0/0.203 point-to-point

ip address x.x.x.x 255.255.255.0

frame-relay interface-dlci 203

class FRTS

interface Serial0/0/0

no ip address

encapsulation frame-relay

frame-relay traffic-shaping

sh traffic-shape

...snip...

Interface Se0/0/0.203

Access Target Byte Sustain Excess Interval Increment Adapt

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

203 128000 160 1280 0 10 160 -

HTH,

jerry

Correct Answer
jbrenesj Tue, 08/18/2009 - 17:24
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10ms is the smallest interval. the default is 150ms.

Bc = Tc * cir

Just don't use the command for tc under the map-class because that's not the way to set a specific interval.

Use the formula and then configure the cir and the Bc

Great help, thanks

I was trying to use

SWRg1(config-map-class)#frame-relay tc 10 ?

but it never worked, now I know why

Jerry Ye Tue, 08/18/2009 - 17:33
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BTW, default CIR is not 150ms, it is 125ms or 1/8 second.

Regards,

jerry