1. Pick up any organization or business or industry and describe a vertical protocol model of it.
2. Explain one of the following protocols how they work
   1. SMTP
   2. SSH
   3. POP
   4. ARP
   5. FTP
   6. telnet
3. Describe the credit scheme used by TCP for flow control
4. How the functions of TCP layers are implemented?
5. What is your understating about the urgent and the push features of TCP?
6. What is the benefit of the three-way handshake mechanism
7. With a reliable sequencing network service, are segment sequence numbers strictly necessary? What, if any, capability is lost without them?