I'm a student of engineering and decided to construct firewall for my major project.Can you provide some ideas about how I should proceed for my topic.I've decide to construct a packet-filtering firewall.
What other kind of firewall is there? Its just a question of how you filter the packets: based on source/dest IP, if TCP/UDP then port, if ICMP then message type, and you can build on top of TCP/UDP by doing deep packet inspection or do about every type of filtering and inspection known to man like project honeypot does.
Either way install linux and learn iptables. I recommend ubuntu.
It would be better to first understand the basic of OSI layer and how things work in various levels..
Later i guess u gotto know about NIDS and NIPS systems (network intrusion detection / prevention systems ) . and finally jump over to something complex as firewall.