Python TCP Server
The TCP server library is also known as the socket library. Socket programming is the method of connecting two nodes through a network to form communication between two nodes. In the two nodes in the circuit, one node will connect to one IP address, and the other end of the connection with another node or socket will connect to the other IP address to form a communication network. These socket connections are the original backbones for web browsing.
When we browse information on the internet, the socket programming will connect to the required IP address. In return, it will be connected to another IP address, and we can observe the output at the interface; this is how the socket programming work.The most common socket programming application is the client-server application. Here, one node of the socket connections consists of the server and another side of the node will give the connection from the client.
The TCP sockets are known as the Transmission Control Protocol servers( TCP ). Generally, in socket programming, first, we need to import the socket library to perform all the operations and then connect the server with the help of modules and the functions available in the socket library.
The Transmission Control Protocol server (TCP) is a socket network in the TCP sockets; the sockets are created using the socket.socket( ) object, and here we need also to specify the socket type, such as a socket.SOCKET_CONNECTION. The sockets which are created using the TCP are reliable. The server reads the packets we will give as input to the TCP server, and these packets are detected and retransmitted back by the sender.
The TCP server has a unique feature; it will read the data in the same order the sender has sent it to the server. The TCP sockets are created to overcome the disadvantage of the UDP sockets; generally, the sockets created by the User Datagram Protocol (UDP)are not reliable, and the data which is read by the receiver is not in the same order as the sender as given as the input that is, the information is out-of-order. So, to overcome these limitations, TCP servers are created.
The networks are the most effective way to transmit data in networking; there is no guarantee that the data is reached its destination or not, but the receiver will receive the data which is sent by the transmitter. Generally, the routers and the switches are known as the network devices, these devices will have a specified bandwidth to transmit the data over a particular distance, but these also have some limitations.
The network devices also consist of the memory devices such as the CPUs and the memory buses to store and transmit the data from sever to the client. The TCP removes the disadvantages such as packet loss, data out-of-order arrival and pitfalls, which will invariably occur when we are trying to communicate across the network.
TCP Socket flow
From the flow chart, we can observe that the data on the left side represents the Server data flow and the data on the right side of the flow chart represents the Client data flow. First, the listening socket will be set in the server column flow chart. It operates the same as the name suggests; it will collect the server's data and then make the connection. With the help of the following functions or methods available in the sock library
- Socket( )
- .bind( )
- .listen( )
- .accept( )
The server collects data from the client and then calls the .accept()function or module, which will connect the data with the server. Then the client will call the .connect( ) function or module, establishing the connection successfully. It follows the three-way handshake process. The handshake step helps connect each side of the network fully.
Hence, the client can reach the server without any problem and can connect easily. The client and the server can send and receive the data with the help of the .send( ) and .receive( )functions. The .bind( )function is used to bind the given data with the server and to transmit it to the client.Finally, after the transmission and receiving of the data, both the client and the server will close their respective sockets.