6. Explain the purpose of block coding and linear block codes in data transmission.

7. Briefly describe the roles of HDLC and PPP in networking.

8. Define Cyclic Redundancy Check (CRC) and explain its role in error detection.  Describe the CRC generation process at the sender's side and receiver side.

9. Define checksum and how does it verify the integrity of data? Explain the process of  checksum creation at the sender's side and receiver side.

10. Define Noiseless Protocol and Explain the types of Noiseless Channel with its  suitable example.

11. Define Noisy Protocol and Explain any two types of Noisy Channel with its suitable  example.