MCQOPTIONS
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MCQOPTIONS
This section includes 406 Mcqs, each offering curated multiple-choice questions to sharpen your Graduate Aptitude Test (GATE) knowledge and support exam preparation. Choose a topic below to get started.
| 101. |
Let the size of congestion window of a TCP connection be 32 KB when a timeout occurs. The round trip time of the connection is 100 msec and the maximum segment size used is 2 KB. The time taken (in msec) by the TCP connection to get back to 32 KB congestion window is _________. |
| A. | 1100 to 1300 |
| B. | 800 to 1000 |
| C. | 1400 to 1600 |
| D. | 1500 to 1700 |
| Answer» B. 800 to 1000 | |
| 102. |
While opening a TCP connection, the initial sequence number is to be derived using a time-of-day(ToD) clock that keeps running even when the host is down. The low order 32 bits of the counter of the ToD clock is to be used for the initial sequence numbers. The clock counter increments once per millisecond. The maximum packet lifetime is given to be 64s. Which one of the choices given below is closest to the minimum permissible rate at which sequence numbers used for packets of a connection can increase? |
| A. | 0.015/s |
| B. | 0.064/s |
| C. | 0.135/s |
| D. | 0.327/s |
| Answer» B. 0.064/s | |
| 103. |
In a communication network, a packet of length L bits takes link L1 with a probability of p1or link L2 with a probability of p2. Link L1 and L2 have bit error probability of b1 and b2 respectively. The probability that the packet will be received without error via either L1 or L2 is |
| A. | (1 - b1)Lp1 + (1 - b2)Lp2 |
| B. | [1 - (b1 + b2)L]p1p2 |
| C. | (1 - b1)L (1 - b2)Lp1p2 |
| D. | 1 - (b1Lp1 + b2Lp2) |
| Answer» B. [1 - (b1 + b2)L]p1p2 | |
| 104. |
Which of the following is not true about User Datagram Protocol in transport layer? |
| A. | Works well in unidirectional communication, suitable for broadcast information |
| B. | It does three way handshake before sending datagrams |
| C. | It provides datagrams, suitable for modeling other protocols such as in IP tunneling or Remote Procedure Call and the Network File System |
| D. | The lack of retransmission delays makes it suitable for real-time applications |
| Answer» C. It provides datagrams, suitable for modeling other protocols such as in IP tunneling or Remote Procedure Call and the Network File System | |
| 105. |
Since it is a network that uses switch, every packet goes through two links, one from source to switch and other from switch to destination. Since there are 10000 bits and packet size is 5000, two packets are sent. Transmission time for each packet is 5000 / 10^7 bits per second links. Each link has a propagation delay of 20 microseconds. The switch begins forwarding a packet 35 microseconds after it receives the same. If 10000 bits of data are to be transmitted between the two hosts using a packet size of 5000 bits, the time elapsed between the transmission of the first bit of data and the reception of the last bit of the data in microseconds is _________. |
| A. | 1075 |
| B. | 1575 |
| C. | 2220 |
| D. | 2200 |
| Answer» C. 2220 | |
| 106. |
In the network 200.10.11.144/27, the fourth octet (in decimal) of the last IP address of the network which can be assigned to a host is ________. |
| A. | 158 |
| B. | 255 |
| C. | 222 |
| D. | 223 |
| Answer» B. 255 | |
| 107. |
A network has a data transmission bandwidth of 20 × 10 6 bits per second. It uses CSMA/CD in the MAC layer. The maximum signal propagation time from one node to another node is 40 microseconds. The minimum size of a frame in the network is _________ bytes. |
| A. | 200 |
| B. | 250 |
| C. | 400 |
| D. | 1200 |
| Answer» B. 250 | |
| 108. |
The maximum window size for data transmission using the selective reject protocol with n-bit frame sequence numbers is: |
| A. | 2^n |
| B. | 2^(n-1) |
| C. | 2^n – 1 |
| D. | 2^(n-2) |
| Answer» C. 2^n – 1 | |
| 109. |
A client message usually needs ........................ to send mail. |
| A. | SMTP |
| B. | POP |
| C. | Both a and b |
| D. | None of these |
| Answer» D. None of these | |
| 110. |
Which one of the following protocols is NOT used to resolve one form of address to another one? |
| A. | DNS |
| B. | ARP |
| C. | DHCP |
| D. | RARP |
| Answer» D. RARP | |
| 111. |
Consider the following statements.I. TCP connections are full duplex.II. TCP has no option for selective acknowledgmentIII. TCP connections are message streams. |
| A. | Only I is correct |
| B. | Only I and II are correct |
| C. | Only II and III are correct |
| D. | All of I, II and III are correct |
| Answer» B. Only I and II are correct | |
| 112. |
Which one of the following uses UDP as the transport protocol? |
| A. | HTTP |
| B. | Telnet |
| C. | DNS |
| D. | SMTP |
| Answer» D. SMTP | |
| 113. |
A DNS.....................server gets its data from another DNS server. |
| A. | Primary |
| B. | Secondary |
| C. | Root |
| D. | All of these |
| Answer» C. Root | |
| 114. |
A program that migrates through networks and operating systems by attaching itself to different Programs and databases is a |
| A. | Virus |
| B. | Worm |
| C. | Denial–of–service attack |
| D. | Damage |
| Answer» B. Worm | |
| 115. |
Consider the following statements: I. telnet, ftp and http are application layer protocols. II.l EJB (Enterprise Java Beans) components can be deployed in a J2EE (Java2 Enterprise Edition) application server. III. If two languages conform to the Common Language Specification (CLS) of the Microsoft.NET framework, then a class defined in any one of them may be inherited in the other. Which statements are true? |
| A. | l and II only |
| B. | II and III only |
| C. | l and III only |
| D. | I, II and III |
| Answer» B. II and III only | |
| 116. |
Suppose the round trip propagation delay for a 10 Mbps Ethernet having 48-bit jamming signal is 46.4 ms. The minimum frame size is |
| A. | 94 |
| B. | 416 |
| C. | 464 |
| D. | 512 |
| Answer» D. 512 | |
| 117. |
Which of the following is not a Block cipher? |
| A. | P - box |
| B. | S – box |
| C. | Pandora’s Box |
| D. | Product block |
| Answer» D. Product block | |
| 118. |
Consider a 128×10 3 bits/second satellite communication link with one way propagation delay of 150 milliseconds. Selective retransmission (repeat) protocol is used on this link to send data with a frame size of 1 kilobyte. Neglect the transmission time of acknowledgement. The minimum number of bits required for the sequence number field to achieve 100% utilization is ___________ |
| A. | 2 |
| B. | 4 |
| C. | 6 |
| D. | 8 |
| Answer» C. 6 | |
| 119. |
Which one of the following statements is FALSE? |
| A. | TCP guarantees a minimum communication rate |
| B. | TCP ensures in-order delivery |
| C. | TCP reacts to congestion by reducing sender window size |
| D. | TCP employs retransmission to compensate for packet loss |
| Answer» B. TCP ensures in-order delivery | |
| 120. |
For which one of the following reasons does Internet Protocol (IP) use the time-to- live (TTL) field in the IP datagram header |
| A. | Ensure packets reach destination within that time |
| B. | Discard packets that reach later than that time |
| C. | Prevent packets from looping indefinitely |
| D. | Limit the time for which a packet gets queued in intermediate routers |
| Answer» D. Limit the time for which a packet gets queued in intermediate routers | |
| 121. |
Identify the correct sequence in which the following packets are transmitted on the network by a host when a browser requests a webpage from a remote server, assuming that the host has just been restarted. |
| A. | HTTP GET request, DNS query, TCP SYN |
| B. | DNS query, HTTP GET request, TCP SYN |
| C. | DNS query, TCP SYN, HTTP GET request |
| D. | TCP SYN, DNS query, HTTP GET request |
| Answer» D. TCP SYN, DNS query, HTTP GET request | |
| 122. |
In a TDM medium access control bus LAN, each station is assigned one time slot per cycle for transmission. Assume that the length of each time slot is the time to transmit 100 bits plus the end-to-end propagation delay. Assume a propagation speed of 2 x 10^8 m/sec. The length of the LAN is 1 km with a bandwidth of 10 Mbps. The maximum number of stations that can be allowed in the LAN so that the throughput of each station can be 2/3 Mbps is |
| A. | 3 |
| B. | 5 |
| C. | 10 |
| D. | 20 |
| Answer» D. 20 | |
| 123. |
A host is connected to a Department network which is part of a University network. The University network, in turn, is part of the Internet. The largest network in which the Ethernet address of the host is unique is: |
| A. | the subnet to which the host belongs |
| B. | the Department network |
| C. | the University network |
| D. | the Internet |
| Answer» E. | |
| 124. |
Having a(n) .....................................is important to help large Organization continue operating until Normal computer operations. |
| A. | Firewall |
| B. | Encryption coding process |
| C. | Disaster recovery plan |
| D. | Virus encrypting programs |
| Answer» D. Virus encrypting programs | |
| 125. |
A subnet has been assigned a subnet mask of 255.255.255.192. What is the maximum number of hosts that can belong to this subnet? |
| A. | 14 |
| B. | 30 |
| C. | 62 |
| D. | 126 |
| Answer» D. 126 | |
| 126. |
Assume that the bandwidth for a TCP connection is 1048560 bits/sec. Let α be the value of RTT in milliseconds (rounded off to the nearest integer) after which the TCP window scale option is needed. Let β be the maximum possible window size with window scale option. Then the values of α and β are |
| A. | 63 milliseconds 65535 × 21^4 |
| B. | 63 milliseconds 65535 × 2^16 |
| C. | 500 milliseconds 65535 × 2^14 |
| D. | 500 milliseconds 65535 × 2^16 |
| Answer» D. 500 milliseconds 65535 × 2^16 | |
| 127. |
The .............................field in the MIME header describes the method used to encode the data. |
| A. | Content – type |
| B. | Content – transfer – Encoding |
| C. | Content – ID |
| D. | Content – description |
| Answer» C. Content – ID | |
| 128. |
In RSA.............................in the common factor in both keys? |
| A. | N |
| B. | e |
| C. | d |
| D. | Mod |
| Answer» B. e | |
| 129. |
Suppose a web server application generates messages consisting of 120 bytes if every second to the Central host, and each message gets encapsulated in a UDP segment and then an IPV4 Datagram. There are no options added in the TCP (or) Ip headers. What percentage of each Datagram will consist of data generated by the application? |
| A. | 81% |
| B. | 75% |
| C. | 25% |
| D. | 20% |
| Answer» B. 75% | |
| 130. |
Suppose that a TCP entity receives 2 MB file from the application layer and the IP layer is willing to Carry blocks of maximum size 1600 B; calculate the amount of overhead incurred from Segmenting the file into packet-sized units. Assume both TCP and Ip header of 20 B. |
| A. | 10% |
| B. | 2.6% |
| C. | 2% |
| D. | 17% |
| Answer» C. 2% | |
| 131. |
Classless Inter-domain Routing (CIDR) receives a packet with address 131.23.151.76. The router’s routing table has the following entries:Prefix Output Interface Identifier131.16.0.0/12 3131.28.0.0/14 5131.19.0.0/16 2131.22.0.0/15 1The identifier of the output interface on which this packet will be forwarded is ______. |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 5 |
| Answer» B. 2 | |
| 132. |
What will be the total minimum bandwidth of the channel required for 7 channels of 400 kHz bandwidth multiplexed together with each guard band of 20 kHz? |
| A. | 2800 khz |
| B. | 2600 khz |
| C. | 3600 khz |
| D. | 2920 khz |
| Answer» E. | |
| 133. |
Which of the following objects can be used in expressions and scriplets in JSP (Java Server Pages) without explicitly declaring them? |
| A. | session and request only |
| B. | request and response only |
| C. | response and session only |
| D. | session, request and response |
| Answer» E. | |
| 134. |
Which one of the following is TRUE about interior Gateway routing protocols - Routing Information Protocol (RIP) and Open Shortest Path First (OSPF)? |
| A. | RIP uses distance vector routing and OSPF uses link state routing |
| B. | OSPF uses distance vector routing and RIP uses link state routing |
| C. | Both RIP and OSPF use link state routing |
| D. | Both RIP and OSPF use distance vector routing |
| Answer» B. OSPF uses distance vector routing and RIP uses link state routing | |
| 135. |
Host X has IP address 192.168.1.97 and is connected through two routers R1 and R2 to another host Y with IP address 192.168.1.80. Router R1 has IP addresses 192.168.1.135 and 192.168.1.110. R2 has IP addresses 192.168.1.67 and 192.168.1.155. The netmask used in the network is 255.255.255.224. Given the information above, how many distinct subnets are guaranteed to already exist in the network? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 6 |
| Answer» D. 6 | |
| 136. |
Which one of the following socket API functions converts an unconnected active TCP socket into a passive socket. |
| A. | connect |
| B. | bind |
| C. | listen |
| D. | accept |
| Answer» D. accept | |
| 137. |
Consider the following statements about the timeout value used in TCP. i. The timeout value is set to the RTT (Round Trip Time) measured during TCP connection establishment for the entire duration of the connection. ii. Appropriate RTT estimation algorithm is used to set the timeout value of a TCP connection. iii. Timeout value is set to twice the propagation delay from the sender to the receiver. Which of the following choices hold? |
| A. | (i) is false, but (ii) and (iii) are true |
| B. | (i) and (iii) are false, but (ii) is true |
| C. | (i) and (ii) are false, but (iii) is true |
| D. | (i), (ii) and (iii) are false |
| Answer» C. (i) and (ii) are false, but (iii) is true | |
| 138. |
There are 15 users communicating to each other. How many pairs of keys are required to authenticate the communications if the symmetric key is used? |
| A. | 15 |
| B. | 30 |
| C. | 105 |
| D. | (15)² |
| Answer» D. (15)² | |
| 139. |
Programs that come into a computer system disguised as something else are called |
| A. | Spoofers |
| B. | Loggers |
| C. | Defacers |
| D. | Trojan horses |
| Answer» E. | |
| 140. |
If a Company require 60 hosts then What is the best possible subnet mask? |
| A. | 255.255.255.0 |
| B. | 255.255.255.192 |
| C. | 255.255.225.224 |
| D. | 225.225.255.240 |
| Answer» C. 255.255.225.224 | |
| 141. |
A link has a transmission speed of 10^6 bits/sec. It uses data packets of size 1000 bytes each. Assume that the acknowledgment has negligible transmission delay, and that its propagation delay is the same as the data propagation delay. Also assume that the processing delays at nodes are negligible. The efficiency of the stop-and-wait protocol in this setup is exactly 25%. The value of the one-way propagation delay (in milliseconds) is ___________. |
| A. | 4 |
| B. | 8 |
| C. | 12 |
| D. | 16 |
| Answer» D. 16 | |
| 142. |
Suppose two hosts use a TCP connection to transfer a large file. Which of the following statements is/are False with respect to the TCP connection?1. If the sequence number of a segment is m, then the sequence number of the subsequent segment is always m+1.2. If the estimated round trip time at any given point of time is t sec, the value of the retransmission timeout is always set to greater than or equal to t sec.3. The size of the advertised window never changes during the course of the TCP connection.4. The number of unacknowledged bytes at the sender is always less than or equal to the advertised window |
| A. | 3 only |
| B. | 1 and 3 only |
| C. | 1 and 4 only |
| D. | 2 and 4 only |
| Answer» C. 1 and 4 only | |
| 143. |
How many bytes of data can be sent in 15 seconds over a serial link with baud rate of 9600 in asynchronous mode with odd parity and two stop bits in the frame? |
| A. | 10,000 bytes |
| B. | 12,000 bytes |
| C. | 15,000 bytes |
| D. | 27,000 bytes |
| Answer» C. 15,000 bytes | |
| 144. |
A computer crime is |
| A. | Any activity in which the thief use the internet |
| B. | An illegal action in which the perpetrator uses special knowledge of computer technology |
| C. | Any crime committed by an AT. Program |
| D. | Any threat to computer or data securi |
| Answer» C. Any crime committed by an AT. Program | |
| 145. |
Which of the following statements are TRUE?(S1) TCP handles both congestion and flow control(S2) UDP handles congestion but not flow control(S3) Fast retransmit deals with congestion but not flow control(S4) Slow start mechanism deals with both congestion and flow control |
| A. | S1, S2 and S3 only |
| B. | S1 and S3 only |
| C. | S3 and S4 only |
| D. | S1, S3 and S4 only |
| Answer» C. S3 and S4 only | |
| 146. |
The subnet mask for a particular network is 255.255.31.0. Which of the following pairs of IP addresses could belong to this network? |
| A. | 172.57.88.62 and 172.56.87.233 |
| B. | 10.35.28.2 and 10.35.29.4 |
| C. | 191.203.31.87 and 191.234.31.88 |
| D. | 128.8.129.43 and 128.8.161.55 |
| Answer» E. | |
| 147. |
An IP machine Q has a path to another IP machine H via three IP routers R1, R2, and R3.Q—R1—R2—R3—H H acts as an HTTP server, and Q connects to H via HTTP and downloads a file. Session layer encryption is used, with DES as the shared key encryption protocol. Consider the following four pieces of information:[I1] The URL of the file downloaded by Q[I2] The TCP port numbers at Q and H[I3] The IP addresses of Q and H[I4] The link layer addresses of Q and H Which of I1, I2, I3, and I4 can an intruder learn through sniffing at R2 alone? |
| A. | Only I1 and I2 |
| B. | Only I1 |
| C. | Only I2 and I3 |
| D. | Only I3 and I4 |
| Answer» D. Only I3 and I4 | |
| 148. |
In the TCP/IP protocol suite, which one of the following is NOT part of the IP header? |
| A. | Fragment Offset |
| B. | Source IP address |
| C. | Destination IP address |
| D. | Destination port number |
| Answer» E. | |
| 149. |
A sender uses the Stop-and-Wait ARQ protocol for reliable transmission of frames. Frames are of size 1000 bytes and the transmission rate at the sender is 80 Kbps (1Kbps = 1000 bits/second). Size of an acknowledgement is 100 bytes and the transmission rate at the receiver is 8 Kbps. The one-way propagation delay is 100 milliseconds. Assuming no frame is lost, the sender throughput is __________ bytes/second. |
| A. | 2500 |
| B. | 2000 |
| C. | 1500 |
| D. | 500 |
| Answer» B. 2000 | |
| 150. |
Match the following:(P) SMTP (1) Application layer(Q) BGP (2) Transport layer(R) TCP (3) Data link layer(S) PPP (4) Network layer (5) Physical layer |
| A. | P – 2 Q – 1 R – 3 S – 5 |
| B. | P – 1 Q – 4 R – 2 S – 3 |
| C. | P – 1 Q – 4 R – 2 S – 5 |
| D. | P – 2 Q – 4 R – 1 S – 3 |
| Answer» C. P – 1 Q – 4 R – 2 S – 5 | |