Computer Networks MCQ Set 1
1. A ___________ is an extension of an enterprise’s private intranet across a public Network such as the Internet across a public Network such as the Internet, creating a secure private connection.
a) VNP
b) VPN
c) VSN
d) VSPN
Answer
Answer: b [Reason:] VIRTUAL PACKET NETWORK.
2. When were VPNs introduced into the commercial world?
a) Early 80’s
b) Late 80’s
c) Early 90’s
d) Late 90’s
Answer
Answer: d [Reason:] LATE 90’S.
3. What protocol is NOT used in the operation of a VPN?
a) PPTP
b) IPsec
c) YMUM
d) L2TP
Answer
Answer: c [Reason:] YNUM.
4. Which of the following statements is NOT true concerning VPNs?
a) Financially rewarding compared to leased lines
b) Allows remote workers to access corporate data
c) Allows LAN-to-LAN connectivity over public networks
d) Is the backbone of the Internet
Answer
Answer: d [Reason:] virtual packet network is not a backbone of the internet.
5. Traffic in a VPN is NOT ____________
a) Invisible from public networks
b) Logically separated from other traffic
c) Accessible from unauthorized public networks
d) Restricted to a single protocol in IPsec
Answer
Answer: c [Reason:] Because it is secured with the IP address.
6. VPNs are financially speaking __________
a) Always more expensive than leased lines
b) Always cheaper than leased lines
c) Usually cheaper than leased lines
d) Usually more expensive than leased lines
Answer
Answer: c [Reason:] It is very cheap.
7. Which layer 3 protocols can be transmitted over a L2TP VPN?
a) IP
b) IPX
c) Neither A or B
d) Both A and B
Answer
Answer: d [Reason:] Data roming layer.
8. ESP (Encapsulating Security Protocol) is defined in which of the following standards?
a) IPsec
b) PPTP
c) PPP
d) L2TP
Answer
Answer: a [Reason:] It is the security type of the IPsec.
9. L2F was developed by which company?
a) Microsoft
b) Cisco
c) Blizzard Entertainment
d) IETF
Answer
Answer: b [Reason:] Cisco is the second best company to design and make the computer networks.
10. Which layer of the OSI reference model does PPTP work at?
a) Layer 1
b) Layer 2
c) Layer 3
d) Layer 4
Answer
Answer: b [Reason:] Presentation layer.
11. Which layer of the OSI reference model does IPsec work at?
a) Layer 1
b) Layer 2
c) Layer 3
d) Layer 4
Answer
Answer: c [Reason:] Session layer.
Computer Networks MCQ Set 2
1. Which of these is not applicable for IP protocol?
a) Connectionless
b) Offer reliable service
c) Offer unreliable service
d) None of the mentioned
Answer
Answer: b [Reason:] IP offers unreliable service.
2. Fragmentation has following demerits
a) Complicates routers
b) Open to DOS attack
c) Overlapping of fragments
d) All of the mentioned
Answer
Answer: d [Reason:] Fragmentation makes the implementation complex and also can create DOS attack.
3. Which field helps to check rearrangement of the fragments?
a) Offset
b) Flag
c) TTL
d) Identifier
Answer
Answer: a [Reason:] offset field specifies where the fragment fits in the original datagram.
4. In classless addressing, there are no classes but addresses are still granted in
a) IPs
b) Blocks
c) Codes
d) Sizes
Answer
Answer: b [Reason:] In classless addressing, there are no classes but addresses are still granted in blocks.
5. In IPv4 Addresses, classful addressing is replaced with
a) Classless Addressing
b) Classful Addressing
c) Classful Advertising
d) Classless Advertising
Answer
Answer: a [Reason:] Classful addressing is replaced with classless addressing.
6. First address in a block is used as network address that represents the
a) Class Network
b) Entity
c) Organization
d) Codes
Answer
Answer: c [Reason:] First address in a block is used as network address that represents the organization.
7. In classful addressing, a large part of available addresses are
a) Organized
b) Blocked
c) Wasted
d) Communicated
Answer
Answer: c [Reason:] In classful addressing, a large part of available addresses are wasted.
8. Network addresses are very important concepts of
a) Routing
b) Mask
c) IP Addressing
d) Classless Addressing
Answer
Answer: c [Reason:] Network addresses are very important concepts of IP addressing.
9. Which of this is not a class of IP address?
a) ClassE
b) ClassC
c) ClassD
d) ClassF
Answer
Answer: d [Reason:] Class F is not a class of IP addressing.
Computer Networks MCQ Set 3
1. The receiver of the data controls the amount of data that are to be sent by the sender is referred as
a) Flow control
b) Error control
c) Congestion control
d) Error detection
Answer
Answer: a [Reason:] Flow control is done to prevent the receiver from being overwhelmed with data.
2. Size of TCP segment header ranges between
a) 16 and 32 bytes
b) 16 and 32 bits
c) 20 and 60 bytes
d) 20 and 60 bits
Answer
Answer: c [Reason:] The header is 20 bytes if there are no options and upto 60 bytes if it contains options.
3. Connection establishment in TCP is done by which mechanism?
a) Flow control
b) Three-Way Handshaking
c) Forwarding
d) Synchronisation
Answer
Answer: b [Reason:] Three-Way Handshaking is used to connect between client and server.
4. The server program tells its TCP that it is ready to accept a connection. This process is called
a) Active open
b) Active close
c) Passive close
d) Passive open
Answer
Answer: d [Reason:] This is the first step in the Three-Way Handshaking process and is started by the server.
5. The process of, A client that wishes to connect to an open server tells its TCP that it needs to be connected to that particular server is
a) Active open
b) Active close
c) Passive close
d) Passive open
Answer
Answer: a [Reason:] This is the second step in the Three-Way Handshaking process and is done by the client once it finds the open server.
6. In Three-Way Handshaking process, the situation where both the TCP’s issue an active open is
a) Mutual open
b) Mutual Close
c) Simultaneous open
d) Simultaneous close
Answer
Answer: c [Reason:] Here, both TCP’s transmit a SYNC+ACK segment to each other and one single connection is established between them.
7. The situation when a malicious attacker sends a large number of SYNC segments to a server, pretending that each of them is coming from a different client by faking the source IP address in the datagrams
a) SYNC flooding attack
b) Active attack
c) Passive attack
d) Denial-of-service attack
Answer
Answer: a [Reason:] This is the serious security problem during the connection establishment.
8. SYNC flooding attack belongs to a type of security attack known as
a) SYNC flooding attack
b) Active attack
c) Passive attack
d) Denial-of-service attack
Answer
Answer: d [Reason:] During SYNC flooding the system collapses and denies service to every request.
9. Size of source and destination port address of TCP header respectively are
a) 16-bits and 32-bits
b) 16-bits and 16-bits
c) 32-bits and 16-bits
d) 32-bits and 32-bits
Answer
Answer: b [Reason:] Size of source and destination ports must be 32-bits.
10. Connection establishment in TCP is done by which mechanism?
a) Flow control
b) Three-Way Handshaking
c) Forwarding
d) Synchronisation
Answer
Answer: b [Reason:] Three-Way Handshaking is used to terminate the connection between client and server.
Computer Networks MCQ Set 4
1. Which of the following is the broadcast address for a Class B network ID using the default subnetmask?
a) 172.16.10.255
b) 255.255.255.255
c) 172.16.255.255
d) 172.255.255.255
Answer
Answer: c [Reason:] This address is used for broadcast the class B network purpose
2. You have an IP address of 172.16.13.5 with a 255.255.255.128 subnet mask. What is your class of address, subnet address, and broadcast address?
a) Class A, Subnet 172.16.13.0, Broadcast address 172.16.13.127
b) Class B, Subnet 172.16.13.0, Broadcast address 172.16.13.127
c) Class B, Subnet 172.16.13.0, Broadcast address 172.16.13.255
d) Class B, Subnet 172.16.0.0, Broadcast address 172.16.255.255
Answer
Answer: b [Reason:] Class B is the address of IP code 172.16.13.5
3. If you wanted to have 12 subnets with a Class C network ID, which subnet mask would you use?
a) 255.255.255.252
b) 255.255.255.255
c) 255.255.255.240
d) 255.255.255.248
Answer
Answer: c [Reason:] If you have eight networks and each requires 10 hosts, you would use the Class C mask of 255.255.255.240. Why? Because 240 in binary is 11110000, which means you have four subnet bits and four host bits. Using our math, we’d get the following:
24-2=14 subnets
24-2=14 hosts.
4. The combination of _________ and __________ is often termed the local address of the local portion of the IP address.
a) Network number and host number
b) Network number and subnet number
c) Subnet number and host number
d) Host number
Answer
Answer: c [Reason:] Sub networking is implemented for remote sensing in transparent way from that a host contains the sub network which called local operation.
5. _________ implies that all subnets obtained from the same subnet mask.
a) Static subnetting
b) Dynamic subnetting
c) Variable length subnetting
d) Both B and C
Answer
Answer: a [Reason:] Static sub network.
6. State whether true or false.
i) A connection oriented protocol can only use unicast addresses.
ii) The any cast service is included in IPV6.
a) True, True
b) True, False
c) False, True
d) False, False
Answer
Answer: a [Reason:] A connection oriented protocol can only use unicast addresses.
The any cast service is included in IPV6.
7. __________ is a high performance fiber optic token ring LAN running at 100 Mbps over distances upto 1000 stations connected.
a) FDDI
b) FDDT
c) FDDR
d) FOTR
Answer
Answer: a [Reason:] FIBER DISTRIBUTED DATA INTERFACE
8. Which of the following are Gigabit Ethernets?
a) 1000 BASE-SX
b) 1000 BASE-LX
c) 1000 BASE-CX
d) a, b, c
Answer
Answer: d [Reason:] In computer networking, Gigabit Ethernet (GbE or 1 GigE) is a term describing various technologies for transmitting Ethernet frames at a rate of a gigabit per second (1,000,000,000 bits per second), as defined by the IEEE 802.3-2008 standard. It came into use beginning in 1999, gradually supplanting Fast Ethernet in wired local networks, as a result of being considerably faster.
9. _________ is a collective term for a number of Ethernet Standards that carry traffic at the nominal rate of 1000 Mbit/s against the original Ethernet speed of 10 Mbit/s.
a) Ethernet
b) Fast Ethernet
c) Gigabit Ethernet
d) All of the mentioned
Answer
Answer: b [Reason:] Fast Ethernet
10. _________ is another kind of fiber optic network with an active star for switching.
a) S/NET
b) SW/NET
c) NET/SW
d) FS/NET
Answer
Answer: a [Reason:] A 50-MBd active star fiber optical Local area network (LAN) and its optical combiner and mixing rod splitter are presented. The limited power budget and relatively large tapping losses of light wave technology, which limit the use of fiber optics in tapped bus LAN topologies, are examined and proven tolerable in optical star topologies.
Computer Networks MCQ Set 5
1. Datagram switching is done at which layer of OSI model?
a) Network layer
b) Physical layer
c) Application layer
d) Transport layer
Answer
Answer: a [Reason:] Datagram switching is normally done at network layer.
2. Packets in datagram switching are referred to as
a) Switches
b) Segments
c) Datagrams
d) Data-packets
Answer
Answer: c [Reason:] As the name suggests, in datagram switching packets are called as datagrams.
3. Datagram networks mainly refers to
a) Connection oriented networks
b) Connection less networks
c) Telephone networks
d) Internetwork
Answer
Answer: b [Reason:] The switch does not keep the information about the connection state, hence it is connection less.
4. Datagrams are routed to their destinations with the help of
a) Switch table
b) Segments table
c) Datagram table
d) Routing table
Answer
Answer: c [Reason:] Routing table is used to route the packets to their destinations.
5. The main contents of the routing table in datagram networks are
a) Source and Destination address
b) Destination address and Output port
c) Source address and Output port
d) Input port and Output port
Answer
Answer: b [Reason:] Routing table contains destination address and output port to route the packets to their destinations.
6. Which of the following remains same in the header of the packet in a datagram network during the entire journey of the packet?
a) Destination address
b) Source address
c) Checksum
d) Padding
Answer
Answer: a [Reason:] Destination address remains same in the header during the entire journey of the packet.
7. Which of the following is true with respect to the delay in datagram networks?
a) Delay is greater than in a virtual circuit network
b) Each packet may experience a wait at a switch
c) Delay is not uniform for the packets of a message
d) All of the mentioned
Answer
Answer: d [Reason:] All the options are true with respect to the delay in datagram networks.
8. During datagram switching, the packets are placed in __________ to wait until the given transmission line becomes available.
a) Stack
b) Queue
c) Hash
d) Routing table
Answer
Answer: b [Reason:] Packets are stored in queue during delay and are served as first in first out.
9. The probability of the error in a transmitted block _________ with the length of the block
a) Remains same
b) Decreases
c) Increases
d) None of the mentioned
Answer
Answer: c [Reason:] Probability of the error in a transmitted block increases with the length of the block.
10. Which of the following is true with respect to the datagram networks?
a) Number of flows of packets are not limited
b) Packets may not be in order at the destination
c) Path is not reserved
d) All of the mentioned
Answer
Answer: d [Reason:] All are the facts with respect to the datagram networks.
