Model which is used to design software for network use is called client server model. A network connection is required between two computers or programs that talk to each other. Network application will be divided into client side and server side in this model. The client side requires information or services and server side responds to client’s requests.
The network application performs two separate well defined functions: requesting information and respond to requested information. Client program requests information and server program responds to the client’s requested information in the client server programming model.
The client and server programming model is a design guide to help programmers to create applications that can smoothly integrate into network communication systems.
ISO/OSI reference model divide the network functions into seven layers and the client/server model divide functions into client side issues and server side issues.
TCP/IP is most important protocol to design networks as well as network applications. TCP/IP is a Transmission protocol /Internet protocol.
Protocol: A protocol is a set of rules which is used by computers to communicate each other in a network. It is a conventional method for network communication. Protocols manage the flow of information between network computers and programs. Protocols specify the rules, which programs must follow to transmit and receive data in an orderly fashion. Protocols are rules which define how software must work. Like, operating systems use rules to handle the flow of data between users, applications and computers, protocols manage the flow of data between network computers and network applications. TCP/IP is a collection protocol suite. The Internet depends on TCP/IP protocol suite which manages all information that moves across the internet. TCP/IP consists of multiple protocols, each of which transfers data across the network in a different format and with different options. Depending on the program’s requirement, it needs to use a specific protocol within the TCP/IP suite to transmit information across the Internet.
IP- The Internet Protocol is a network layer protocol that moves data between host computers
TCP- The Transport Control Protocol is a transport layer protocol which moves data between applications
UDP- The User Datagram Protocol is another transport-layer protocol. UDP also moves data between applications. However, UDP is less complex and less reliable than TCP.
ICMP- The Internet Control Message Protocol carries network error messages and reports other conditions that require attention by network software.