1) Make a group of the OSI layers by function.

2) What do you mean by header and trailers and how do they get added and removed?

3) The transport layer generates a communication between source and destination. What are the three events involved in the connection?

4) What do you mean by the DC component?

5) How does NRZ-L differ from NRZ-I?

6) Encode the bit stream 10000000000100 using HDB3. Suppose number of 1s so far is odd and the first 1 is positive.

7) prepare down the functions of a DTE? What are the functions of a DCE?

8) What does the electrical specification of EIA-232 describe?

9) Describe the mode for propagating light along optical channels in detail.

10) What do you mean by refraction?

11) prepare down the advantages and drawbacks of bus topology.

12) prepare down the advantages and drawbacks of ring topology.