Hi,
Then either the UDP packet was fragmented or the capture was limited to a
certain length, not including all data. In these cases also Wireshark can't
verify the checksum, hence can't say it's either good or bad.
Thanx,
Jaap
Yuxin Zhuang wrote:
> Hi, Jaap,
>
> Thanks for your reply!
>
> But the content of Checksum is not 0x0000. The output is as follows:
> Checksum: 0xd87e
> Good Checksum: False
> Bad Checksum: False
>
> I can't figure out whether the checksum is correct or not. Lots of other packets' checksum are not zero either and the result is similar.
>
> Thanks,
> Yuxin
>
> -----Original Message-----
> From: wireshark-users-bounces@xxxxxxxxxxxxx [mailto:wireshark-users-bounces@xxxxxxxxxxxxx] On Behalf Of Jaap Keuter
> Sent: 2009锟斤拷2锟斤拷2锟斤拷 14:00
> To: Community support list for Wireshark
> Subject: Re: [Wireshark-users] No indication about UDP checksum
>
> Hi,
>
> In UDP the checksum is optional. So if it's set to 0x0000 that means it's not calculated by the sender and cannot be checked by the receiver.
> For Wireshark that results in "Checksum: 0x0000 (none)" and it can't be neither good or bad, since there's is no checksum.
>
> Thanx,
> Jaap
>
> Yuxin Zhuang wrote:
>> Hi,
>>
>> While i'm analyzing some captured pkts, i notice that lots of UDP pkts
>> have no indication on 'checksum' and both good and bad checksum are
>> 'false'. What does this mean?
>>
>> The output is as follows:
>>
>>
>> Thanks a lot!
>> Yuxin
>>