Setting the QOS by using policing command in C-3550 ?

[mark_chen]

Dear All,

My problem is how should i couculate the brst rate when i try to set the incoming traffic to 1Mbps in 3550 by using the policing command ?

Thanks.

Mark

[spremkumar]

Hi

Basically policing uses Token bucket system to calculate the dropping stragety once the packets exceeds the limit.it has single and dual token bucket system in which you will mention the CIR,burst rate and the exceed burst rate.

the bc is actually calculated using the forumla

Burstmin (bits) = Rate (bps) / 8000 (1/sec)

u can set the burst rate either 8000bps or 32000bps based on ur requirement.the below mentioned link will ofcourse get u more about the same.

http://www.cisco.com/en/US/products/hw/switches/ps646/products_tech_note09186a00800feff5.shtml

regds

[mark_chen]

Hi,

Thank you for your help!

I'd read that document before and I did just like what you said, but somehow I can't fit my guarantee rate(1Mbps) when I tested by using FTP or IPerf etc. The test result always showed me 100~200 (bits per second),it's more less than 1Mbps as I set. So how should I change the burst rate to fit just what I need??

You may refer the configuration below as what I did.

Thanks,

Mark

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class-map match-all test

match access-group 100

!

policy-map test

class test

police 1000000 32000 exceed-action drop

!

access-list 100 permit ip x.x.x.x any

!

interface FastEthernet0/1

switchport access vlan 101

switchport mode access

load-interval 30

duplex full

service-policy input test

spanning-tree portfast

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