Cisco 3945 and Cisco 2921 comparison

[patrimar]

Dear all,

Hope you are doing well.

I am searching information about the size of the input hardware buffer of a router interface, but I can't find anything. Could anybody tell me that value on a Cisco 3945 platform and a Cisco 2921 platform?

Thank you so much.

Patricia

[Leo Laohoo]

Depends on what you're doing, Patricia.  

Have you seen the document entitled Router Performance before?  This is the final "version" of this PDF file because the team responsible for publishing this document got dissolved in 2012.  It was too bad because a number of people use this document as a "bible".  

[patrimar]

  Thank you so much Leo, I will read it now.

  We are doing a throughput test with a Cisco 2921. We are obtaining good results, but there are some overruns at WAN interface.

  We are going to substitute this device for a Cisco 3945 and we are corcerned about if we are going to obtain worse results. We suppose that a Cisco 3945 is better than a Cisco 2921 in performance, but according to the 'show buffer' output, the Cisco 3945 has 768 of private buffer and the Cisco 2921 has 1024 of private buffer. 

  Could somebody explain me this difference? You wait that Cisco 3945 has more private buffer than Cisco 2921.

  Thanks in advance.

  Patricia

[Leo Laohoo]

We are doing a throughput test with a Cisco 2921. We are obtaining good results, but there are some overruns at WAN interface.

Exactly what is your WAN speed?

[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.

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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

Patricia, you're a Cisco employee (?), and you asking for public hardware specifications?  Laugh, I would have thought you should have better sources of (internal) technical product information.

In any case, besides Leo's references, Cisco has published the attached document for the performance of the later ISRs.  It doesn't answer your question about input buffers, but if you're comparing 2921 and 3945 performance, maybe you'll find it useful.

[patrimar]

I'm so happy to make you laugh, Joseph. I was not so happy this last weekend, having a 5 hours call with the customer, working all Sunday searching information to give them an answer on Monday in the morning. I was searching information by my own, I opened a TAC case and I asked for Community colaboration; as you can see, I opened several ways of investigation because I had little time.

Thank you for the white paper, I knew it.

Regards,

Patricia

[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

Patricia, upon reflection, it's not laughable, but instead, really sad that a Cisco employee, when dealing with a Cisco customer, needs to resort to public support forums for providing Cisco device information.  (I applaud your effort, though.  Does Cisco?)

As to your personal unhappiness, working all Sunday, well if you're not satisfied with your working conditions, it might be time to dust off the old resume.

[Leo Laohoo]

you're a Cisco employee (?), and you asking for public hardware specifications?

This ain't the first and won't be the last time.  Go over to the "Wireless" section of the forum and you'll see we get a few.  :)  :)

Heck, go over to the "Wireless" section and we even have rampant Cisco contractors (from Sales Acceleration Team) pretending to post solutions but posting wrong solutions.  

[patrimar]

Thank you so much, I have obtained the information by other means.