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.

What is computer network? Describe the Network Crieteria.

 Define protocol and Standards in Computer networks.

Write short notes on (any two):

i) Packet Switching

ii) Circuit Switching

iii) HTTP

iv) FDDI

What is CIDR? How does CIDR contribute to address aggregation?

 What is Cryptography? Distinguish between passive and active attacks.

Describe Diffie-Hellman key exchange. Let p = 23. g = 5. Alice picks a = 6, Bob picks b = 15. Find the shared key.

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.

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

Explain the process of creating and verifying a digital signature using asymmetric key cryptography. Use a step-by-step example involving a sender and a receiver.

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

 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.

Describe Diffie-Hellman key exchange. Let p = 23. g = 5. Alice picks a = 6, Bob picks b = 15. Find the shared key.

What is Distance Vector Routing? Use distance vector algorithm to construct routing table for node C in the Fig. 2.

 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.

 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 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.

What is symmetric key encryption? Compare symmetric and asymmetric encryption with examples.

Alice uses a mobile app to hide messages in image pixels. Is this encryption or steganography? Explain.

Write short notes on (any two):

i) Packet Switching

ii) Circuit Switching

iii) HTTP

iv) FDDI

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

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

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.

Write short notes on (any two):

i) Packet Switching

ii) Circuit Switching

iii) HTTP

iv) FDDI

What is HMAC? How does it ensure message integrity? Does it encrypt the message content?

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

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?

Define subnetting. An organization is assigned the block 172.30.0.0/16. It wants to create 256 subnets.

i) Find the subnet mask

ii) Find the number of addresses in each subnet

iii) Find the first and last addresses in subnet 10

iv) Find the first and last addresses in subnet 256

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

 What are the differences between IPv4 and IPv6 addressing?

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?

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

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

What is the difference between a pubiic IP and a private IP? Provide examples of each.

You are transmitting a 5000-byte datagram over a link with MTU = 1500 bytes. Calculate how many fragments are created and show offset values.

In an IPv4 datagram, the value of total-length field is (00A0)16 and the value of the header length (HLEN) is (5)16. How many bytes of payload are being carried by the datagram? What is the efficiency (ratio of the payload length to the total length) of this datagram?

Write any two advantages and disadvantages of using IPv6 over IPv4.

What is the difference between IPv6 link-local and unique local addresses? Provide examples.

What is tunneling in IPv6? Give an example scenario where tunneling is required.

Write any two advantages and disadvantages of using IPv6 over IPv4.

Define ICMP and explain how it is used in error reporting and diagnostics.

You are transmitting a 5000-byte datagram over a link with MTU = 1500 bytes. Calculate how many fragments are created and show offset values.

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.

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

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

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

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

 What is Cryptography? Distinguish between passive and active attacks.

Define ICMP and explain how it is used in error reporting and diagnostics.

What is CIDR? How does CIDR contribute to address aggregation?

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

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.

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

What is protocol needed? For n devices in a network, what is the number of cable links required for a mesh, ring, bus, and star topology?

 What is Cryptography? Distinguish between passive and active attacks.

Describe Diffie-Hellman key exchange. Let p = 23. g = 5. Alice picks a = 6, Bob picks b = 15. Find the shared key.

What is HMAC? How does it ensure message integrity? Does it encrypt the message content?

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.

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

Define Network Security. Differentiate between spoofing and sniffing attacks.

What is protocol needed? For n devices in a network, what is the number of cable links required for a mesh, ring, bus, and star topology?

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

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

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

List the responsibilities of Transport Layer and Network Layer in the Internet Model.

How does information get passed from one layer to the next in the Internet model?

 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.

 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?

Explain the responsibilities of the session and transport layer in the Internet model?

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?

Derive the routing table for the following Fig. 1. Also, show the forwarding process if a packet 5 arrives at R1 with the destination address 180.70.65.140.

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

Briefly describe: Destination-based forwarding and Source-based forwarding.

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.

A switch uses a filtering table; a router uses a routing table. Can you explain the difference?

Write short notes on (any two):

i) Packet Switching

ii) Circuit Switching

iii) HTTP

iv) FDDI

 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.

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?

Derive the routing table for the following Fig. 1. Also, show the forwarding process if a packet 5 arrives at R1 with the destination address 180.70.65.140.

 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.

A switch uses a filtering table; a router uses a routing table. Can you explain the difference?

 Describe about the shift cipher and transposition ciphers with example.

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.

Explain the process of flow control in TCP using the sliding window mechanism.

 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.

Alice uses a mobile app to hide messages in image pixels. Is this encryption or steganography? Explain.

What is subnetting? An organization is granted the block 211.17.180.0/24. The administrator wants to create 32 subnets. i) Find the subnet mask ii) Find the number of addresses in each subnet iii) Find the first and last addresses in subnet 1 iv) Find the first and last addresses in subnet 32

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

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?

Define subnetting. An organization is assigned the block 172.30.0.0/16. It wants to create 256 subnets.

i) Find the subnet mask

ii) Find the number of addresses in each subnet

iii) Find the first and last addresses in subnet 10

iv) Find the first and last addresses in subnet 256

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

 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.

Explain the process of flow control in TCP using the sliding window mechanism.

What is congestion? Explain the slow start algorithm used in TCP congestion control with a suitable example.

 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.

Explain the responsibilities of the session and transport layer in the Internet model?

 Describe about the shift cipher and transposition ciphers with example.

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

What are the three criteria necessary for an effective and efficient network? Draw a hybrid topology with a ring backbone and three bus networks.

What is protocol needed? For n devices in a network, what is the number of cable links required for a mesh, ring, bus, and star topology?

What is protocol needed? For n devices in a network, what is the number of cable links required for a mesh, ring, bus, and star topology?

What is indirect packet delivery? Discuss about network specific and host specific packet forwarding techniques.

An ISP is granted a block of addresses starting with 190.100.0.0/16 (65,536 addresses). The ISP needs to distribute these addresses to three groups of customers as follows:

i) The first group has 64 customers; each need 256 addresses.
ii) The second group has 128 customers; each need 128 addresses.
iii) The third group has 128 customers; each need 64 addresses.

Design the subblocks and find out how many addresses are still available after these allocations.

List the limitations/disadvantage of each layer of OSI model.