marshaling
data copying
control transfer
protocol transfer
Three copies
-client stub
-kernel buffer
-dma to controller
Reducing copies?
-marshal into kernel buffer directly
-shared descriptors between client stub and kernel
Routing on the internet
Application
transport
network
link
physical
network, link, physical
App payload|qos
protocol stack++
IP-hdr code payload
dst dst dst
Potential Apps
protocol independent multicast
reliable multicast
congestion notification
private ip(PIP)
any casting
