Re: How PAT works

Hi Divin,

  Thanks for the comment ...The below makes sense but the one which I was
trying to understand was about ron responed "pat won't use well known
application ports",to avoid cnfusion with the data traffic.

Once again thanks for the explanation .

Regards
Anantha Subramanian Natarajan
On Fri, Aug 28, 2009 at 12:21 PM, Divin Mathew John <divinjohn_at_gmail.com>wrote:

> its something todo with
> PAT (overloading) divides the available ports per global IP address into
> three ranges: 0-511, 512-1023, and 1024-65535. PAT assigns a unique source
> port for each UDP or TCP session. It will attempt to assign the same port
> value of the original request, but if the original source port has already
> been used, it will start scanning from the beginning of the particular port
> range to find the first available port and will assign it to the
> conversation.
>
> On Fri, Aug 28, 2009 at 10:42 PM, Anantha Subramanian Natarajan <
> anantha.natarajan_at_gravitant.com> wrote:
>
>> Hi All,
>>
>> I was going through the NAT FAQ link as pasted below to understand how
>> PAT
>> works in cisco devices.I was able to understand the explanation stated
>> except the below point highlighted.What is the meaning of that ?..Kindly
>> help me to understand the same.
>>
>>
>> http://www.cisco.com/en/US/tech/tk648/tk361/technologies_q_and_a_item09186a00800e523b.shtml#qa12
>>
>> *"If PAT knows about the traffic type, and that traffic type has "a set of
>> specific ports or ports it negotiates" that it will use, PAT sets them
>> aside
>> and does not allocate them as unique identifiers"*
>> **
>> Thanks for the help
>>
>> Regards
>> Anantha Subramanian Natarajan
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
>> _______________________________________________________________________
>> Subscription information may be found at:
>> http://www.groupstudy.com/list/CCIELab.html
>>
>>
>>
>>
>>
>>
>>
>>
>
>
> --
>
> Sent from Cochin, KL, India
> Dalton Camp <http://www.quotationspage.com/quote/26252.html> - "Politics
> is made up largely of irrelevancies."

Blogs and organic groups at http://www.ccie.net
Received on Fri Aug 28 2009 - 12:30:43 ART