Computer Networ...

If in CIDR notation an IP address is written as 172.26.17.1/25 the subnet mask is:

Consider a network, in which the data transmission rate is 10 Mbps. It uses CSMA/CD in the MAC layer. The maximum signal propagation time from one node to another node is 50 microseconds. What is the minimum size of a frame in the network?

A block of addresses is granted to a small organization. If one of the addresses is 210.32.64.79/26, then what will be the values of the following?

(i) First address

(ii) Last address

Let a source S be sender sending packets to destination D using stop and wait protocol. S needs to send 500 packets to D while error occurs during sending the packets is 20%. The total number of packets sent by S is _____.

Consider a designed link layer protocol. The bandwidth of the link is 2 gigabits per second. The length of the fibre link is 5 ×10⁵ m. If the speed of the light in the given medium is 250000 kilometre per second then the propagation delay of the link is _____ ms.

Your router has the following IP address a Ethemet0: 172.16.2.1/23. Which of the following can be valid host IDs on the LAN interface attached to the router?

1. 172.16.1.100

2. 172.16.1.198

3. 172.16.2.255

4. 172.16.3.0

Consider a binary code that consists of only 5 valid codewords as given below.

10111, 00011, 10110, 11111 and 00001

P is the minimum Hamming distance and Q is the maximum Hamming distance. The number of P and Q possible are _____ and _____ respectively.

Consider a classful addressing scheme in which the percentage (%) of IP address covered by Class A is x and by Class C is y. What is the value of x + y? 

Consider the following application layer services:

(a) Domain names to IP Address mapping

(b) Data Communication over World Wide Web

(c) Electronic mail transmission

(d) Retrieve e-mail from a remote server

(e) Transfer files from one host to another host

Consider a long-lived TCP session, for which the end-to-end bandwidth 4 Gb/s. The session starts with a sequence number of (0000)₁₆ . The minimum time in seconds before this sequence number can be used again is _____.

Note: answer up to one decimal places)

If the data frame is 1101011011 and the divisor is 10011 in a CRC error detection process, a burst error 0000010011 occurs in transmission, Justify whether it will be detected:

Consider the following set of statements:

1. The physical layer is concerned with the connection of the devices to the media.

2. The data link layer defines the direction of transmission between two devices.

3. The transport layer can be either connectionless or connection-oriented.

Which of the above statements is/are true?

The value of the expression 23²³⁷ (mod 29), in the range 0 to 28, is______. 

The size of the congestion window of a TCP connection is 64 KB when a timeout occurs. The round trip time of the connection is 20 msec and the maximum segment size used is 2 KB. What is the time taken (in msec) by the TCP connection to get back to 64 KB congestion window?

An IP router implementing Classless Inter-domain Routing (CIDR) receives a packet with address 210.128.22.67. The router’s routing table has the following entries:

On which interface packet will be forwarded?

In an RSA cryptosystem, the value of the public modulus parameter n is 15251. If it is also known that φ(n) = 15000, where φ() denotes Euler’s Totient Function, then the smallest prime factor of n is _____. (Hint: one of the prime factors of n is less than 200 and greater than 150)

Consider the following statements about leaky bucket and token bucket algorithm.

I. In leaky bucket algorithm, network interface transmits packets at a constant rate.

II. The token bucket algorithm is less restrictive than the leaky bucket algorithm.

III. The implementation of leaky bucket algorithm is simple.

Which of the above statement is correct?

Consider two hosts,a frame of size 1000 byte is sent over 30 Mb/s duplex link between them. Frames are to be transmitted into this link to maximally pack them in transit. The propagation time is 100 milliseconds. What is the minimum number of bits that will be required to represent the sequence numbers distinctly?

Let the two host X and Y connected via a packet switch with 10⁷ bits per second links. Switch is placed at 50 km from X. X and Y are located at 100 Kilometer apart also the propagation speed along the link is 2 × 10⁸ m/s. The switch begins forwarding a packet after 0.1 milliseconds it receives the packet. If 1000 bytes of File are needed to be transmitted and each packet size is 500 bytes, the time elapsed between the transmission of the first bit of data and the reception of the last bit of the data in millisecond is _____.

Consider the following three statements about link state and distance vector routing protocols, for a large network with 500 network nodes and 4000 links.

[S1] The computational overhead in link state protocols is higher than in distance vector protocols.

[S2] A distance vector protocol (with split horizon) avoids persistent routing loops, but not a link

state protocol.

[S3] After a topology change, a link state protocol will converge faster than a distance vector

protocol.

Which one of the following is correct about S1, S2, and S3?

In a network two systems are connected and are separated by 400 km. The bandwidth of the network is 40 × 10⁷ bytes per second. The propagation speed of the media is 2 × 10⁷ meters per second. In given network, Go-Back-N sliding protocol is used with maximum network capacity. Packet size is 16 × 10⁶ bits and processing delay at nodes are negligible. Then the minimum size in bits of the sequence number filed of sender is _____.

Consider three machines X, Y, and Z with IP address 200.20.15.3, 200.20.15.1, and 200.20.15.2 respectively. The subnet mask is set to 255.255.255.254 for all the three machines. Which one of the following is true?

Consider an IP packet with a data length of 4400 bytes. TCP header is of 40 bytes while that of IPv4 header is 20 bytes. The packet is forwarded to an IPv4 router that supports MTU of 900 bytes. Length of the IP header for outgoing fragments is 20 bytes. Assume that the fragment offset value stored in the first fragment is 100.

Let X and Y be the two stations on an Ethernet and both stations have a ready state of frames to send. Both X and Y attempt to transmit a frame, collide, and no one wins the race. What is the probability that neither X nor Y wins the next back-off race?