Wireshark · Wireshark-users: Re: [Wireshark-users] Capture hardware

[Hansang Bae <hbae@xxxxxxxxxx>]

Kok-Yong Tan wrote:
[snip]
> I know that Laura Chappell mentioned in Sharkfest 2008 the need for  
> special tools for gigabit packet capture and that gigabit NICs won't  
> work (I'm a newbie to gigabit packet capture so I'm not clear about  
> the details since Ms. Chappell made cheetahs look like turtles during  
> Sharkfest--can someone enlighten me as to why a single gigabit NIC  
> will not work for full-duplex gigabit packet capture?  Does it have  
> to do with it being lossy due to the speed of the NIC overwhelming  
> the speed of the data bus on most computers?)

Imagine this:
PC sends 1Gbps  ---(TX)---->  to Server
PC receives     <--(RX)----- 1Gbps from the server.


Now you span TX and RX to *one* Gigabit NIC.  You cannot fit 2Gbps worth 
of traffic to a 1Gb NIC.




--

Thanks,
Hansang