Java Distributed Computing

Anatomy of a Distributed Application

A distributed application is built upon several layers. At the lowest level, a network connects a group of host computers together so that they can talk to each other. Network protocols like TCP/IP let the computers send data to each other over the network by providing the ability to package and address data for delivery to another machine. Higher-level services can be defined on top of the network protocol, such as directory services and security protocols. Finally, the distributed application itself runs on top of these layers, using the mid-level services and network protocols as well as the computer operating systems to perform coordinated tasks across the network.

At the application level, a distributed application can be broken down into the following parts:

Processes

A typical computer operating system on a computer host can run several processes at once. A process is created by describing a sequence of steps in a programming language, compiling the program into an executable form, and running the executable in the operating system. While it’s running, a process has access to the resources of the computer (such as CPU time and I/O devices) through the operating system. A process can be completely devoted to a particular application, or several applications can use a single process to perform tasks.

Threads

Every process has at least one thread of control. Some operating systems support the creation of multiple threads of control within ...