What is computer network? Describe the Network Crieteria.

What are the advantages of a multi-point connection over a P2P connection?

 Define protocol and Standards in Computer networks.

 What do you mean by ARPANET? Describe the physical topology of computer networks.

In the Go-Back-N protocol, the size of the send window can be 2m - 1, while the size of the receive window is only 1. How can flow control be accomplished when there is a big difference between the size of the send and receive windows? Briefly Explain.

 If the data link layer can detect errors between hops, why do you think we need another checking mechanism at the transport layer in the OSI Model? What is a socket address? Compare TCP and UDP protocols.

What do you mean by loopback interface? An organization is assigned the block 2000:1456:2474/48. What is the IPv6 address of an interface in the third subnet if the IEEE physical address of the computer is (F5-A9-23-14-7A-D2)₁₆?

You are given the following network address and subnet mask:

Network address: 192.168.10.0

Subnet mask: 255.255.255.252

i) How many subnets?

ii) How many hosts?

iii) What are the valid subnets

iv) Fill in the table below

 If the data link layer can detect errors between hops, why do you think we need another checking mechanism at the transport layer in OSI model?

 How can NAT help in address depletion? Explain with necessary diagram.

 What is Cryptography? Distinguish between passive and active attacks.

What are the differences between message confidentiality and message integrity? Can you have one without another? Use the additive cipher with k = 5 to encrypt the plaintext "BU". Then decrypt the message to get the original plaintext.

Consider sending 4000-byte IP datagram (including the 20 bytes IP header) into a link that has an MTU of 1200 bytes. Determine the values of the length field and the offset field in each fragment.

Derive the routing table for the following Fig. 1. Can router R1 in Fig. 1 receive a packet with destination address 140.24.7.194? What will happen to the packet if this occurs?

Show abbreviations for the following IPv6 addresses:

i) 1234:0000:3456:0000:A058:0000:0000:F02F

ii) 0000:0001:0000:0000:0000:56E2:24.120.12.90

 List three forwarding techniques and give a brief description of each.

What is Frame Relay? What is Frame Relay a better solution for connecting LANs tha T-1 lines?

 What are the differences between IPv4 and IPv6 addressing?

Briefly define sub-netting and super-netting. How do the subnet mask ad super-net mask differ from a default mask in classful addressing?

How does Frame Relay control congestion? What attributes are used for traffic control in Frame Relay?

 What is RSA algorithm? Alice wants to send message a to Bob. Then Bob need to select keys. Suppose, Bob chosen p = 7 and q = 13 in the RSA algorithm. Now, find the value of d. Also, encrypt the message "CSE" using Bob's public key so that he can only decrypt. For simplicity, do the encryption and decryption character by character.

What is Digital Signature? How it can be implemented to provide message integrity service?

The following shows the IPv6 datagram format. Compare it with IPv4 datagram format.

 Describe about the shift cipher and transposition ciphers with example.

 What do you mean by the "Two-Node Loop Instability" problem with distance vector routing? Explain with necessary diagrams. Also, provide a solution to the problem.

Write short notes on (any two):

i) Packet Switching

ii) Circuit Switching

iii) HTTP

iv) FDDI