The Life and Times of a Network Request
This seems like an awful lot of work, but it’s an excellent example of why layering is important. Each layer knows only what it absolutely must about the layers above and below it, making it possible to swap out the innards of layers if desired. When a new physical protocol is created, the other layers don’t have to care; the logical protocol just hands the request off to the physical protocol layer and lets that layer do its thing. When you have a new type of network card, all you need to do is write a driver that interfaces with the physical protocol; the application and logical protocol layers don’t care. [2]Unless, of course, some of it breaks, in which case your managers will want to know exactly what sort of equipment it is, how long it will take to repair, and why you need it anyway. Page 162
Note: If you are looking for good and affordable webspace to host and run your servlet application check Virtualwebstudio servlet hosting services