Hi,

> Hi,
>
> I am going to do some video streaming experiments over wireless
> networks. I try to get the corrupted video bitstream from  network, but
> the PPP and UDP checksum discard the corrupted packets. WinPcap can get
> the packet before it is sent to upper layer protocols.In this case,
> maybe I can get the corrupted packet from network. My questions are:
>
>  (1)Does WinPcap support PPP with higher windows service pack?

No if winpcap is used upon the ndiswan MS driver. As Q6
http://winpcap.polito.it/misc/faq.htm states, the problem is in ndiswan
rather than in winpcap.
You have some chances to capture the packets if the adapter is emulated as
an ethernet device (which I think is the usual case for most adapters).

>  (2)if the packet is corrupted before it is sent to PPP, can the
> WinPcap pick up the corrupted packet?

As far as I know, no. The corrupted layer 2 frames are usually discarded by
the hardware or by the NIC driver.

>  (3)Can I get the packet as soon as it arrives the wireless card?

Yes. Again, unless winpcap is used upon the ndiswan MS driver. In this case
you will get nothing.

>  (4)Does WinPcap do some check sum while it decode PPP and UDP packet?

No, it delivers all the packets it sees, without any processing.


Loris

>  Thanks a lot for your early reply.
>
>  Best wishes
>
>  Yufeng
>
> The wireless card I will use is Sierra Wireless AirCard 555.
> www.sierrawirelss.com
>
>
>

Reply via email to