A new language concept–communication port (CP), is introduced for programming on distributed processor networks. Such a network can contain an arbitrary number of processors each with its own private storage but with no memory sharing. The processors must communicate via explicit message passing. Communication port is an encapsulation of two language properties: "communication non-determinism" and "communication disconnect time." It provides a tool for progranmers to write well-structured, modular, and efficient concurrent programs. A number of examples are given in the paper to demonstrate the power of the new concepts.