tune linux ip stack?

[Stefhen Hovland <stefhen.hovland@gmail.com>]

Does anyone have any tips or relevant links for tuning the Linux IP stack?

About the only url I have found is:
http://www.psc.edu/networking/projects/tcptune/

About the only thing I have found to change in this link above were:

       	echo 8388608 > /proc/sys/net/core/wmem_max 
       	echo 8388608 > /proc/sys/net/core/rmem_max 
       	echo "4096 87380 4194304" > /proc/sys/net/ipv4/tcp_rmem
       	echo "4096 65536 4194304" > /proc/sys/net/ipv4/tcp_wmem


I am still recieving suboptimal usenet downloads from
news.giganews.com even after  the 4mbps Comcast speed upgrade my city
went through a couple of months ago, and I am wanting to know if there
are any other tunable parameters I should look into which could be
affecting my download speed.

Any suggestions?

Thanks,
Stefhen