Process-to-process delivery
Process-to-process delivery is the first task of the Transport layer protocol.
In process-to-process communication, the transfer of data takes place between two individual processes executing on end systems, which is done using port numbers or addresses. Port numbers help identify which process is sending or receiving on a host.
Two processes can communicate through client/server relationships.
Client/Server Paradigm
The Client/Server paradigm is one of the many ways to obtain process-to-process communication. It divides the software into two categories- clients and servers. A client is software that sends requests, and the server processes the requests.
In UDP programming no actual connection is established, while in TCP connections are established between the machines, hence the client/server paradigm is much more relevant.
Multiplexing and Demultiplexing
Multiplexing is a process that can combine the multiple processes occurring at the sender’s site.
In demultiplexing, the multiple processes that have been combined into one are separated into many processes.
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