[Winpcap-users] Winpcap and NIC chipsets

[Stefano Bonetti]

Hi all,
we are using the Winpcap library inside a low-latency audio/visual 
streaming system named "LoLa"
(http://www.conts.it/artistica/lola-project/lola-low-latency-audio-visual-streaming-system). 

More precisely we are using Winpcap to send about 55300 packet per 
second with the pcap_sendqueue_queue and pcap_sendqueue_transmit 
commands; each packet is 1000 bytes in size and the Lan speed is 1Gbit.
The system performs very well (so thanks for you great job) but we have 
noticed a different behavior using
some network adapters. With the Realtek or Marvell chipsets we are able 
to send/receive only half of the packets,
but when we use Intel NICs we are able to send and receive all the 
packets (no drops and with the network monitor
showing, correctly, 98% of utilization); for our project it means that 
we are sending/receiving a video stream at
60fps (uncompressed RGB, 24bit, 640x480).
The Intel chipsets are 82574 and 82579 … we have tested many computers 
with the same result and the same
behavior occurs even using the MS Winsock libraries, so it does not seem 
to be a problem related specifically to
the winpcap library but generally to the NICs chipset.

Has someone had similar experiences in the past or perhaps some 
suggestions on how to improve the network
performance for Realtek/Marvell (or generally "low-cost") network chipset?

Thanks in advance,
Stefano Bonetti
LoLa team developer