Re: UDP checksum calculation - uses lenght twice ?

Tech-Archive recommends: Fix windows errors by optimizing your registry

BTW all calculations you can take from
http://www.codeguru.com/network/tcpip_lib31.html
Arkady

"Arkady Frenkel" <arkadyf@xxxxxxxxxxxxxxxx> wrote in message
news:O$6MlgA9FHA.808@xxxxxxxxxxxxxxxxxxxxxxx
> But I wrote *why* you need that : if your packet went to other IP (
> machine e.g. router too ) by mistake that checksum ( only routing data )
> will tell that destination is wrong . That used both in TCP and UDP the
> same and if you see my messages ( as others ) and I see yours - sure that
> done OK :)
>
> Arkady
>
> "R.Wieser" <address@xxxxxxxxxxxxx> wrote in message
> news:OKL7qaA9FHA.4076@xxxxxxxxxxxxxxxxxxxxxxx
>> Arkady Frenkel <arkadyf@xxxxxxxxxxxxxxxx> schreef in berichtnieuws
>> e7DADr#8FHA.2192@xxxxxxxxxxxxxxxxxxxxxxx
>>
>> Hello Arkady,
>>
>>> Additionally , on RFC793 that starts on last line of page 15 and
>>> continue
>> to
>>> page 16 :
>>>
>>> The checksum also covers a 96 bit pseudo header conceptually
>>
>> Thanks for your responses. Yes, I saw that one too. However, none of
>> the
>> "this is how you calculate the checksum for ...." tell me anything about
>> the
>> *why* of using the UDP-length double :-( :-)
>>
>> By the way : the sending & recieving of the UDP-packets to/from a
>> Windows-machine goes o.k., so I guess the checksum-calculation is o.k
>> too.
>> :-)
>>
>> Regards,
>> Rudy Wieser
>>
>>
>>
>
>


.

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