Summary

Since TCP/IP is likely to be around for a while, you need to be familiar with its layers, processes, and functions. TCP/IP is a popular network protocol choice. The Process/Application layer includes many protocols that interface with the users’ programs. The Host-to-Host layer is responsible for connection-oriented or connectionless communication. The Internet layer includes IP and its error reporting protocol ICMP and the resolution protocols ARP and RARP.

Connection-oriented TCP/IP applications rely on TCP and the guarantee of delivery, whereas connectionless applications use UDP and are often described as best-effort delivery. Internet layer protocols of the TCP/IP suite are responsible for logical addressing, address assignment, and logical-to- physical address resolution. Physical addresses are assigned by the NIC manufacturer and map to a logical address at the Internet layer.

The Novell protocol suite includes upper layer protocols responsible for routing and network services. At the Transport layer, you’ll find SPX, which is equivalent in function to TCP and IPX at the Network layer and is used for logical addressing, much like IP.

IPX addressing is used by all IPX-network-assigned devices but includes the logical and physical address, eliminating the need for further resolution.