# MANGLE
iptables -t mangle -m tos --tos 16 -A PREROUTING -p tcp --dport www
# I don't allow it but in case you do 
iptables -t mangle -m tos --tos 16 -A PREROUTING -p tcp --dport telnet
iptables -t mangle -m tos --tos 16 -A PREROUTING -p tcp --dport ftp
# for max throughput
iptables -t mangle -m tos --tos 8 -A PREROUTING -p tcp --dport ftp-data