Module 4

14 Questions

What type of transfer does UDP offer from client to server?

Unreliable and unordered

What does the client provide when creating a socket?

The server's IP address and port number

What happens during the TCP handshake when the client initially contacts the server?

The server generates a new socket for the client

What is the purpose of the welcoming socket in TCP?

To serve as the initial point of contact for all clients

How many sockets are created for each TCP client that contacts the server?

One socket for each client

What type of transmission does TCP offer between the client and server processes?

Reliable and sequential byte-stream

What is a socket in the context of network communication?

One endpoint of a two-way communication link between two programs on a network

What is the purpose of a port number in a socket?

To associate the socket with a specific process or service

What is the key difference between connection-oriented and connectionless sockets?

The need for an explicit connection setup before data transmission

What protocol is used by connectionless sockets?

UDP

What information does a client need to initiate a connection request to a server?

The server's IP address and port number

What happens to data transmitted via UDP if there is no connection setup?

It may be lost or arrive out of order

What is the role of the server in establishing a connection?

The server binds to a local port number and awaits connections

How do servers extract the client's IP address and port number in UDP?

Explicitly specified by the client

Study Notes

Sockets

A socket represents one endpoint of a two-way communication link between two programs on a network, associated with a specific port number.
Each endpoint consists of an IP address and a port number.
In every TCP connection, two endpoints are identified, enabling multiple connections between hosts and servers.

Types of Sockets

Connection-oriented sockets establish a direct link between two socket endpoints, utilizing the Transmission Control Protocol (TCP) to ensure reliable data delivery.
Connectionless sockets operate without the need for an explicit connection setup before data transmission, using the User Datagram Protocol (UDP) for faster data delivery.

Socket Creation and Communication

For a connection request, the client needs the server machine's IP address and port number.
The server initiates a socket, binds it to a local port number, and then awaits connections.
Once a connection is established, communication between client and server occurs through socket read and write operations.

Socket Programming with UDP

In UDP, there is no connection setup between client and server, and no initial handshaking is required before communication.
Clients explicitly specify the server's IP address and port number, and servers extract the client's IP address and port number.
Data transmitted between client and server via UDP can be lost or arrive out of order.

Socket Programming with TCP

For communication to begin, the client initiates contact with the server, which must be operational and prepared to receive connections.
The client creates a socket, providing the server's IP address and port number.
During the TCP handshake, the server generates a new socket specifically for communicating with that client.
A new socket is created for each TCP client that contacts the server, and this new socket is dedicated to communication with that client throughout the entire TCP connection.
The TCP connection offers reliable and sequential byte-stream transmission between the client and server processes.