Question regarding Qos policing token buckets

[prabhu.natarajan]

Hi,

Went through several documents about policing and shaping features.one question that came to my mind on policing. we know policing use single token bucket and dual token buckets (BC and BE). for example CIR traffic is coming in and buket (consider sigle bucket) doesnt have enough tokens to pass the traffic so that time what policing will do. In Shaping i believe tokens are put into buckets at Tc interval, if there is no enough bukcets to pass traffic, will wait for Tc interval and bucket will enough tokens to pass traffic (please correct me here if i am wrong in Shaping also).

As per policing, it fill up the buckets whenever it does policing and fill up the bucket. For some reason, it doesnt have tokens to pass traffic. what it will do.. In case of dual buckets, it will look into second bucket and look for tokens to pass traffic. if there is no enough tokens in second bucket also. what it will do..

Please help me understanding this

Thanks,

Seeni

[Joseph W. Doherty]

Disclaimer

The  Author of this posting offers the information contained within this  posting without consideration and with the reader's understanding that  there's no implied or expressed suitability or fitness for any purpose.  Information provided is for informational purposes only and should not  be construed as rendering professional advice of any kind. Usage of this  posting's information is solely at reader's own risk.

Liability Disclaimer

In  no event shall Author be liable for any damages whatsoever (including,  without limitation, damages for loss of use, data or profit) arising out  of the use or inability to use the posting's information even if Author  has been advised of the possibility of such damage.

Posting

With policers, if they don't have sufficient tokens to pass packet, it's dropped.  With shapers, packet is queued.

[prabhu.natarajan]

Hi,

Do u mean to say policer will drop the traffic if there is no enough tokens in buckets even it is CIR traffic coming in to be allowed?

Thank you for your time

Thanks,

Seeni

[Joseph W. Doherty]

Disclaimer

The   Author of this posting offers the information contained within this   posting without consideration and with the reader's understanding that   there's no implied or expressed suitability or fitness for any purpose.   Information provided is for informational purposes only and should not   be construed as rendering professional advice of any kind. Usage of  this  posting's information is solely at reader's own risk.

Liability Disclaimer

In   no event shall Author be liable for any damages whatsoever (including,   without limitation, damages for loss of use, data or profit) arising  out  of the use or inability to use the posting's information even if  Author  has been advised of the possibility of such damage.

Posting

Yes, because if traffic was CIR (according to the policer) it wouldn't have used all its tokens.