Useful Links:

1. Historical stuff

2. Some classic papers

3. General publications

4. Real systems

5. Reference materials

    IP over anything

    The classic IP

    IP forwarding

    TCP and UDP basics

   TCP congestion control

   DNS    HTTP     Intra-domain routing protocols

    Inter-domain routing protocols

    Firewalls     Other protocols

   Reliability and security of the Internet infrastructure

6. Others