Network Programming Sockets Python TCP,UDP Beginner friendly exercises

1. Network programming in Python
M.DHIVYASHREE

2. Socket
 A socket is an endpoint of a two-way communication link between
two programs running on a network.
 It allows data to be sent and received between devices, just like
plugging a cable into a port.
 Sockets are the foundation of network programming in Python.
 Socket programming in Python involves using sockets to establish
communication between a server and clients over a network.

3. What comprises in a socket?

4. How sockets actually work?

5. Types of Sockets in Python
 Stream Socket (TCP)
 Datagram Socket (UDP)

6. Stream Socket (TCP)
•Uses Transmission Control Protocol
•Connection-oriented
•Reliable delivery (data reaches in order, without loss)
•Used for: web servers, chat applications, file transfer

7. Datagram Socket (UDP)
•Uses User Datagram Protocol
•Connectionless
•Faster but not reliable
•Used for: gaming, video streaming, real-time updates

8. Two layers for network programming
1. Low-Level Networking (Socket Layer)
2. High-Level Networking (Protocol Libraries)

9. Low-Level Networking (Socket
Layer)
 At the foundational level, Python gives direct access to the
operating system’s socket interface.
 With this, you can manually build networking applications by
controlling every detail of the connection.
 This level allows you to create both:
1. Connection-oriented communication (e.g., TCP)
2. Connectionless communication (e.g., UDP)
 In this layer, you work with raw sockets, manage IP addresses and
ports yourself, and handle sending/receiving data packets directly.

10. High-Level Networking (Protocol
Libraries)
 Above the socket layer, Python provides modules that implement
common internet protocols for you.
 Instead of managing sockets manually, you can directly use ready-
made tools to interact with:
1. HTTP (via urllib, requests)
2. FTP (via ftplib)
3. SMTP (via smtplib)
4. And other application-level protocols
 This layer simplifies tasks like downloading web pages, sending
emails, or transferring files because it hides the low-level socket
operations behind user-friendly APIs.

12. Server Program (server.py)

13. Client Program (client.py)

14. How to Run?
1. Save both codes in two files:
server.py
client.py
2. Run server:
python server.py
3. Run client (in another terminal):
python client.py
4. You will see messages exchanged between server and client.

15. Simple Python Socket Programming Exercises
 Exercise 1: Print a Message from Client to Server
 Exercise 2: Send Your Name to the Server
 Exercise 3: Two-Number Addition