Java™ Network Programming and Distributed Computing

1.4. Advantages of Layering

The division of network protocols and services into layers not only helps simplify networking protocols by breaking them into smaller, more manageable units, but also offers greater flexibility. By dividing protocols into layers, protocols can be designed for interoperability. Software that uses Layer n can communicate with software running on another machine that supports Layer n, regardless of the details of Layer n-1, Layer n-2, and so on. Lower-level layers, for example, can be substituted and replaced without having to modify or redesign higher-level layers, or recompile application software. For example, a network layer protocol can work with an Ethernet network and a token ring network, even though at the physical ...