CN NP

 Assignment 1

1.A router works in

1. Physical Layer

2. Data Link Layer

3. Network Layer

4. Transport Layer

Ans:Network Layer

2.Which of the following network device is used for interconnecting two LANs working on the same protocol?

1. Repeater

2. Hub

3. Bridge

4. None of these

Ans:Bridge

3.Which of the following is a transport layer protocol?

1. SMTP

2. UDP

3. ICMP

4. SSH

Ans:UDP

4.In which layer NICs work?

1. Network Layer

2. Data Link Layer

3. Transport Layer

4. Application Layer

Ans:Data Link Layer

5.Which of the following network device filters network traffic based on the MAC addresses?

1. Bridge

2. Router

3. Repeater

4. Hub

Ans:Bridge

6.Telephone system network is the one of example of

1. Circuit switching

2. Packet switch

3. None of these

Ans:Circuit Switching

7.A file of 'x bits' is sent from host A to host B over a circuit switched network that uses TDM with 'h slots’ and have a bit rate of 'R Mbps'. The circuit establish time is k seconds. Find the

total time

1. (x*h)/R secs 

2. ((x*h/R + k) secs

3. (x)/R secs

4. (x/R+k) secs

Ans:((x*h/R + k) secs

8.A Datagram switching is a

1. Connection-oriented packet switching 

2. Connectionless packet switching

3. None of these

Ans:Connectionless packet switching

9.Which protocol is used to acquire the MAC address of a host whose IP address is known?

1. Dynamic Host Control Protocol

2. Address Resolution Protocol

3. User Datagram Protocol

4. None of these

Ans:Address Resolution Protocol

10.Which of these following protocol prevents out-of-order delivery of data?

1. DNS

2. UDP

3. TCP

4. None of these

Ans:TCP

Assignment 2

1.Which of the following is a remote login application?

1. Telnet

2. DNS

3. SMTP

4. FTP

Ans:Telnet

2.Which of the following network management command is used for querying the DNS?

1. Netstat

2. Nslookup

3. whois 

4. None of these

Ans:Nslookup

3.Which of the following file is used to configure DNS in the client side?

1. Hosts

2. Nsswitch.conf

3. Resolv.conf

4. ntp.conf

Ans:Resolv.conf

4.Which of the following system call puts the server socket in a passive mode and waits for the client to approach the server to make a connection?

1. Connect

2. Accept

3. Listen

4. bind

Ans:Listen

5.FTP control connection is initiated on port number

1. 20

2. 21

3. 80

4. 143

Ans:21

6.HTTP cookie is stored in

1. user's computer

2. Server

3. None of these

Ans:user's computer

7.Which port does HTTP use in transport layer?

1. 80

2. 443

3. 20

4. 21

Ans:80

8.Telnet does not use any security mechanism and transfers the data over network internet in a plain-text form including the passwords.

1. True

2. False

Ans:True

9.SMTP servers commonly use the TCP on port number

1. 21

2. 22

3. 23

4. 25

Ans:25

10.SNMP is an application layer protocol which is used to

1. transfer mail from one user to another

2. monitor the network, detect network faults etc.

3. move files between local and remote file systems

4. transports messages between devices

Ans:transports messages between devices

Assignment 3

1.Which of the following layer provides host-to-host communication services for      applications?

1. Data Link Layer

2. Network Layer

3. Transport layer

4. Application Layer

Ans:Network Layer

2.Datagram mode communication used by the IP and UDP protocols, where data may be      delivered out of order.

1. True

2. False

Ans:True

3.Which of the following is a reliable protocol?

1. TCP

2. UDP

3. None of these

Ans:TCP

4.Congestion control prevents senders from overwhelming the_____________

the sender from overwhelming the__________________

1. receiver, network

2. network, receiver

3. sender, receiver d. None of these

Ans:network, receiver

5.To establish a connection, TCP uses a three way handshake because both sender and receiver need to synchronize their segment sequence numbers used during their transmission

1. True

2. False

Ans:True

6.The Protocol Data Unit (PDU) of the transport layer is called

1. Packet

2. Bit

3. Frame

4. Segment

Ans:Segment

7.The ------------------ field contains the next segment that the sender of the acknowledgement expects to receive.

1. Sequence number

2. Acknowledgment number

Ans:Acknowledgment number

8.In ----------------, duplicate packets from a previous connection (which has been closed) between the two nodes might still be floating on the network

1. 2-way handshake

2. 3-way handshake

Ans:2-way handshake

9.Which of the following is the correct statement?

1. TCP is unreliable, IP is unreliable

2. TCP is reliable, IP is reliable

3. TCP is unreliable, IP is reliable

4. TCP is reliable, IP is unreliable

Ans:TCP is reliable, IP is unreliable

10.Which of the following is the correct statement?

1. Go Back N ARQ rejects out-of-order packets

2. In Selective Repeat ARQ, out-of-order delivery can not happen

3. In Go Back N ARQ. number of retransmissions in case of packet drop is 1

4. In Stop and Wait ARQ, lost data problem is resolved by sequence number

Ans:Go Back N ARQ rejects out-of-order packets

Assignment 4

1.Consider the bandwidth as 50 Kbps, one way transit time=240 msec and the segment size is 1000 bit. Consider the event of a segment transmission and the corresponding ACK reception Find the maximum number of segments that can be outstanding during this duration.

1. 23

2. 24

3. 25

4. 26

Ans:25

2.In the sender, application data is sent from the transport layer to the IP layer by the --- call. 

1. read()

2. write()

3. receive()

Ans:write()

3.Sender and receiver needs to dynamically adjust buffer allocations for

1. flow control

2. congestion control

3. Reliability

4. connection establishment

Ans:flow control

       Congestion control

4.Transport layer is implemented in

1. User space

2. Kernel

Ans:Kernel

5.In order to avoid congestion, the sending rate should be

1. <=receiver rate

2. maximum(network rate, receiver rate)

3. <=network rate

4. minimum(network rate, receiver rate)

Ans:minimum(network rate, receiver rate)

6.If congestion is detected, the AIMD algorithm

1. decreases sending rate additively

2. increases sending rate multiplicatively

3. decreases sending rate multiplicatively

4. increases sending rate additively

Ans:decreases sending rate multiplicatively

7.------- uniquely identifies an application within a computer.

1. Port number

2. IP address

Ans:Port number

8.TCP supports multicasting.

1. True

2. False

Ans:False

9.TCP segments are of same size

1. True

2. False

Ans:False

10.TCP sequence number field is of

1. 8 bit

2. 16 bit

3. 24 bit

4. 32 bit

Ans:32 bit

Assignment 5

1.TCP uses a sliding window flow control algorithm with go back N ARQ principle.

1. True

2. False

Ans:True

2.How long does the receiver wait before it sends a delayed acknowledgment for receiving

    few more packets?

1. RTT

2. 2*RTT

3. 250 ms

4. 500 ms

Ans:500ms

3.Nagle's algorithm states that send a short packets in a TCP connection unless the    

   previous short packets are acknowledged by the receiver.

1. True

2. False

Ans:False

4.Whenever the receiver advertises a large window size, silly window syndrome

    happens.

1. True

2. False

Ans:False

5.The solution to silly window syndrome problem is are

1. Nagle's algorithm

2. Clark's solution

3. Jacobson's algorithm

4. None of these

Ans:Nagle's algorithm

       Clark's solution

6.TCP stores the out of order data if there is space in receiver window, and sends a

duplicate ACK.

1. True

2. False

Ans:True

7.Jacobson's algorithm is used to

1. solve silly window syndrome problem

2. handle out of order data problem

3. calculate dynamic time out timer

Ans:calculate dynamic time out timer

8.Which of the following TCP timers avoid deadlock when receiver buffer is

   announced as zero?

1. Time wait timer

2. Retransmission timer

3. Keepalive timer

4. Persistent timer

Ans:Persistent timer

9.Karn's Algorithm ignores retransmitted segments when updating the round-trip

   time estimate.

1. True

2. False

Ans:True

10.In the slow start phase in TCP congestion control the congestion window is

     increased

1. Linearly

2. Exponentially

3. none of these

Ans:Exponentially

Assignment 6

1.The network layer doesn't guarantee delivery of each packet, and doesn't promise to

   deliver them in the same order.

1. True

2. False

Ans:True

2.Which of the following protocol is used by the routers to send error messages when

   communicating with another IP address?

1. IP

2. ICMP

3. MQTT

4. NTP

Ans:ICMP

3.What is the maximum number of hosts that can be attached to a Class A in the IPv4

  addressing system ?

1. 2^16

2. 2^16 - 2

3. 2^24

4. 2^24 - 2

Ans:2^24 - 2

4.The address of a class B host is to be split into subnets with a 6-bit subnet number. What    

    is the maximum number of subnets and the maximum number of hosts in each subnet?

1. 62 subnets and 262142 hosts.

2. 64 subnets and 262142 hosts.

3. 62 subnets and 1022 hosts.

4. 64 subnets and 1024 hosts

Ans:62 subnets and 1022 hosts

5.Given IP Address : 172.16.0.0/25, find the number of subnets and the number of hosts per

   subnet.

1. 514 subnets and 128 hosts per subnet

2. 512 subnets and 126 hosts per subnet

3. 514 subnets and 126 hosts per subnet

4. 512 subnets and 128 hosts per subnet

Ans:512 subnets and 126 hosts per subnet

6.In the IPv4 addressing format, the number of networks allowed under Class C addresses    

   is

1. 2^14

2. 2^7

3. 2^21

4. 2^24

Ans:2^21

7.Suppose computers A and B have IP addresses 10.105.1.113 and 10.105.1.91    

   respectively and they both use the same netmask N. Which of the values of N given below    

   should not be used if A and B should belong to the same network?

1. 255.255.255.0

2. 255.255.255.128

3. 255.255.255.192

4. 255.255.255.224

Ans:255.255.255.224

8.NAT can help to balance the load of multiple identical server accessible from a single IP

   address.

1. True

2. False

Ans:True

9.IPv6 supports broadcast mechanisms.

1. True

2. False

Ans:False

10.Which of the following is/are not a valid IPv6 address?

1. AE82::1:800:23E7:F5DB

2. FC80:2:7:1:800:23E7:A:FSDB

3. DE62:6A42: 1:5AC::800:23E7-F5DB

4. AEC6: 1:600:23E7F5DB

Ans:AEC6: 1:600:23E7F5DB

Assignment 7

1.Here two computers are connected via a link. The bandwidth of the link is 4Mbps (1Mbps -   

  10 bits per second) and the delay is 500milliseconds. Assume that you are sending a SMIB   

  (1Mebibyte (MIB) - 2"bytes) file from A to B. What will be the transmission delay and the 

   propagation delay?

1. Transmission delay: 0.5sec, propagation delay: 1.51509 sec

2. Transmission delay: 10.48576sec, propagation delay: 0.5sec

3. Transmission delay: 4sec, propagation delay: 1.31072

4. Transmission delay: 1.31072sec, propagation delay: 4sec

Ans:Transmission delay: 10.48576sec, propagation delay: 0.5sec

2.What is a service level agreement?

1. It is the agreement to maintain constant bitrate.

2. It is the agreement to maintain a reliable connection between two hosts.

3. It is the agreement to maintain QoS.

4. It is the agreement to maintain connectivity

Ans:It is the agreement to maintain QoS.

3.What does traffic shaping do in QoS?

1. It regulates the incoming traffic rate.

2. It regulates the outgoing traffic rate.

3. It prioritizes the outgoing flow as per policy.

4. It prioritizes the incoming flow as per policy.

Ans:It regulates the outgoing traffic rate.

4.Assume there is a token buffer traffic shaper with token arrival rate r and bucket size t. If  

   packets arrive in bursts with a burst interval of time t and an arrival rate of p, what is the        

   maximum departure rate from the traffic shaper?

1. P

2. r

3. b/t

4. (p+rt)/t

Ans:p

5.Given the arrival rate in the table, how long will it take to clear the traffic with a leaky   

   bucket traffic shaper having a leak rate of Spkt per sec and bucket size 20pkts. How many 

   packets does it need to drop?

1. 12.4 sec, 20 packets dropped

2. 13.4 sec, 15 packets dropped

3. 14.4 sec, 10 packets dropped

4. 15.4 sec, 5 packets dropped

Ans:15.4 sec, 5 packets dropped

6.What is (are) true for Intserv and DiffServ?

1. DiffServ provides Qos by differentiating traffic based on the information available in the packet while IntServ provides Ons based on the service agreement

2. IntServ architecture is suitable for the Internet-scale service while DiffServ provides guaranteed end-to end Qos.

3. DullServ aware routers Implement per-hop Qos behaviors while IntServ maintains end-to end Qos by resource reservation

4. Bandwidth broker is required in IntServ architecture while RSVP is required for DiffServ architecture

Ans:DiffServ provides Qos by differentiating traffic based on the information available in the    

       packet while IntServ provides Ons based on the service agreement

       DullServ aware routers Implement per-hop Qos behaviors while IntServ maintains   

       end-to end Qos by resource reservation

7.What is true for a resource reservation protocol?

1. It is a routing protocol

2. It tries to reserve the required resources throughout the path

3. RSVP demon talks to only remote routing protocol daemon.

4. RSVP daemon runs in all the devices including end hosts and intermediate routers

Ans:It tries to reserve the required resources throughout the path

       RSVP daemon runs in all the devices including end hosts and intermediate routers

8.What happens in traffic classification and conditioning?

1. Mapping packets to a forwarding class supported in the next DS domain

2. Choosing the correct path for a packet to forward to the next network 

3. Reserving the resources in next JS domain to provide IntServ.

4. None of the above

Ans:Mapping packets to a forwarding class supported in the next DS domain

9.Random Early Detection (RED) queue is used to

1. avoid congestion in the network before it occurs.

2. drop random packets from the queue to make space for a new packet.

3. provide fair queuing among the different classes of traffic.

4. smooth out drop probability across all the flows.

Ans:avoid congestion in the network before it occurs.

       smooth out drop probability across all the flows.

10.Why is TCP traffic elastic traffic?

1. TCP sends traffic at a constant rate.

2. TCP adjusts traffic rate based on congestion.

3. TCP maintains end-to-end flow control.

4. None of the above

Ans:TCP adjusts traffic rate based on congestion.

Assignment 8

1.What does the router do?

1. Route packets from one port to another in the same sub-network.

2. Route packets from one network to another network.

3. The router is another name of the HTTP server, it serves web pages.

4. None of the above.

Ans:Route packets from one network to another network.

2.What is the network address for the following IP addresses:

   i) IP Address: 10.5.27.15, IP Mask: 255.255.248.0

   ii) IP Address: 172.18.12.100, IP Mask: 255,240.0.0

   Select the correct option

1. i) 10.5.24.0, ii) 172.18.12.0

2. i) 10.5.27.0, ii) 172.18.12.0

3. i) 10.5.24.0, ii) 172.16.0.0

4. i) 10.5.27.0, ii) 172.16.0.0

Ans:i) 10.5.24.0, ii) 172.16.0.0

3.How does the router decide the destination if multiple entries in routing tables match with   

   the destination address?

1. It picks the first one,

2. It picks the destination with the longest prefix matching

3. It picks the destination with the shortest prefix matching

4. It picks the last matched destination

Ans:It picks the destination with the longest prefix matching

4.What are the correct statements in the context of an autonomous system (AS)?

i) A transit AS carries traffic from one AS to another.

ii) Transit AS is by default multi-home AS.

iii) A stub AS can not carry any transit traffic

Select the correct options

1. ii

2. iii & ii

3. ii & i 

4. i & iii

Ans:i & iii

5.For the following network, what will be the routing table information for node E lf we use a  

   link-state routing protocol?

Ans:

6.RIP is a

1. Distance vector routing protocol.

2. Link state routing protocol.

3. Path vector routing protocol.

4. Hybrid routing protocol.

Ans:Distance vector routing protocol

7.Select the correct statements.

i) Every AS need two different sets of routing protocol.

ii) BGP is an interior gateway routing protocol.

iii) Exterior gateway protocol exchanges information between ASs.

iv)OSPF can be used as EGP.

1. iv & iii

2. iv & i

3. ii & iii

4. iii & i

Ans:iii & i

8.How does the exterior gateway routing protocol (EGP) differ from the interior gateway   

   routing protocol (IGP)?

1. Flooding is not feasible in EGP

2. Network policies need to be implemented for EGP but are not needed for IGP

3. Loop prevention is not required for EGP.

4. IGP need to know the complete path.

Ans:Flooding is not feasible in EGP

       Network policies need to be implemented for EGP but are not needed for IGP

9.BGP communication packet types are

1. SYNC

2. OPEN

3. UPDATE

4. FINISH

5. NOTIFICATION

6. KEEPALIVE

Ans:OPEN

       UPDATE

       NOTIFICATION

       KEEPALIVE

10.Which of the following data structure is better suited for the longest prefix matching?

1. RB tree

2. Heap

3. Patricia tree

4. All

Ans:Patricia tree

Assignment 9

1.A router contains two hardware components, a router processor and multiple network interfaces. Match the task done by these different hardwares.

Tasks: i) execution of routing protocol, ii) FIB lookup, iii) maintenance of routing table 

iv) packet forwarding. v) route calculations

1. Router processor: iii, v, i; Network interfaces: i, iv

2. Router processor: iii, ii, i; Network interfaces: v, iv

3. Router processor: ii, iv, i; Network interfaces: iii, v

4. Router processor: iii, v, iv; Network Interfaces: ii, i

Ans:Router processor: iii, v, i; Network interfaces: i, iv

2.Which is true for Forwarding Information Base (F18)?

1. It resides at the RAM

2. In a specialized hardware. It is implemented using TCAM.

3. It contains a subset of the routing table.

4. The routing table is a subset of the FIB

Ans:In a specialized hardware. It is implemented using TCAM.

       It contains a subset of the routing table.

3.which of these statements are true?

1. RAM Is accessed via the content while CAM is accessed via the address where the content is stored

2. CAM is optimized for performing a query on the content while RAM is optimized to fetch and store data based on the address

3. CAM can be used to search forwarding host in one cycle while RAM needs linear search or Patricia tree

4. None of the above are true

Ans:CAM is optimized for performing a query on the content while RAM is optimized to fetch    

       and store data based on the address

       CAM can be used to search forwarding host in one cycle while RAM needs linear      

       search or Patricia tree

4.A router needs to be configured in a way such that it forwards all packets whose destination IPs are in the range of 172.24.0.0 to 172.25.255.255 to the gateway 192.168.2.38 through the interface enp0s2.

Select the correct command

1. ip route add 172.24.0.0/15 dev enp0s2

2. ip route add 172.24.0.0 via 192.168.2.38/16 dev enp0s2

3. ip route add 172.24.0.0/16 via 192.168.2.38 dev enp0s2 

4. ip route add 172.24.0.0/15 via 192.168.2.38 dev enp0s2

Ans:ip route add 172.24.0.0/15 via 192.168.2.38 dev enp0s2

5.Which options are true for SDN?

1. SDN moves the control plane to a centralized server.

2. Switches in the SDN need to be very smart.

3. All the traffic in the SDN needs to go through the controller.

4. The switches contact SDN when a packet does not match with any of the existing rules.

Ans:SDN moves the control plane to a centralized server.

       The switches contact SDN when a packet does not match with any of the existing rules.

6.Select the OpenFlow controller.

1. NS3

2. Ryu

3. OMNET++

4. OpenDayLight

Ans:Ryu

       OpenDayLight

7.) What is the advantage of using a network emulator over a network simulator?

1. Emulator allows calculating things that have to go through the network instead of actually sending them

2. It allows the user to set up an arbitrary network in a single hardware

3. it can be used in real network applications.

4. A Mathematical model can be executed without implementing them in a real network

Ans:It allows the user to set up an arbitrary network in a single hardware

       it can be used in real network applications.

8.How to create the following network using mininet command?

1. mn --topo single,3,4

2. mn --topo single,4,3

3. mn --topo linear,3,4

4. mn --topo linear,4,3

Ans:mn --topo linear,4,3

9.What is true for the north-bound interface in SDN?

1. North-bound interface communicates traffic with the higher plane in the SDN.

2. Communication between data plane and control plane happens via the north-bound interface.

3. All the automation and orchestration of the system takes place via the north-bound interface.

4. The controller controls the packet through a north-bound interface.

Ans:North-bound interface communicates traffic with the higher plane in the SDN

       All the automation and orchestration of the system takes place via the north-bound i     

       interface.

10.What does a data-plane do?

1. Decide where to send a packet based on a central policy

2. Forward the data packet

3. Configure the hardware

4. None of them

Ans:Forward the data packet

Assignment 10

1.What is the difference between MAC sublayer and LLC sublayer?

1. LLC multiplexes data from network layer and demultiplexes data to network layer, MAC layer provides mechanism to access the physical medium to receive and transmit data

2. LLC allows a network device to be uniquely identified in a LAN, MAC multiplexes data from network layer and demultiplexes data to network layer,

3. LLC is optional if error control is not required, MAC is optional If flow control is not required. 

4. LLC provides flow control and error control over two devices in a LAN, MAC layer uniquely identifies a network card in a LAN

Ans:LLC multiplexes data from network layer and demultiplexes data to network layer, MAC  

       layer provides mechanism to access the physical medium to receive and transmit data

       LLC provides flow control and error control over two devices in a LAN, MAC layer   

       uniquely identifies a network card in a LAN  

2.As per 802.3 standard, what is the length of MAC address?

1. 128 bits

2. 32 bits

3. 48 bits

4. none of them

Ans:48 bits

3.Which options are true?

1. CSMA/CD should be used when the transmitter and the receiver can not be turned on simultaneously

2. CSMA/CD have less collision probability than that of Aloha

3. Slotted Aloha does not sense before sending data

4. A node can start transmitting data only at beginning of a slot in slotted aloha

Ans:CSMA/CD have less collision probability than that of Aloha

Slotted Aloha does not sense before sending data

A node can start transmitting data only at beginning of a slot in slotted aloha

4.Aloha (slotted or pure) used lIn wireless medium because---

1. It is not always possible to detect collision apriori due to hidden node 

2. It can detect collision faster than CSMA/CD

3. It detects hidden nodes before transmitting data

4. it clears the paths before any transmission

Ans:It is not always possible to detect collision apriori due to hidden node 

5.What is the difference between a repeater and a hub?

1. A repeater relays/amplifies/regenerates incoming signals and forwards. Hub forwards incoming signal to all the outgoing ports

2. A repeater allows multiple computers to be connected. A hub increases the coverage of a signal.

3. A repeater is an analog device, while a hub is a digital device

4. Multiple repeaters can be connected in the form of a chain to increase range, multiple hubs can be connected in the form of a tree to connect more devices

Ans:A repeater relays/amplifies/regenerates incoming signals and forwards. Hub forwards  

       incoming signal to all the outgoing ports

       Multiple repeaters can be connected in the form of a chain to increase range, multiple 

       hubs can be connected in the form of a tree to connect more devices

6.What are the properties of switched ethernet?

1. Filter segments based on IP address

2. High utilization of computer networks

3. Unencrypted data leakage can be avoided

4. Collision rate is very high

Ans:High utilization of computer networks

Unencrypted data leakage can be avoided

7.What does preamble do In an ethernet frame?

1. Provides packet-level synchronization

2. Provides frame level synchronization

3. Provides byte-level synchronization

4. Provides bit-level synchronization

Ans:Provides bit-level synchronization

8.What is true for bridged ethernet?

1. Collision is not at all possible in bridged ethernet

2. Bridged ethernet breaks the collision domain by separating LAN 

3. Bridged network reduce the overall throughput as result of excess overhead

4. Bridge networks efficiency lesser than that of switched network

Ans:Bridged ethernet breaks the collision domain by separating LAN

Bridge networks efficiency lesser than that of switched network

9.What is the purpose of random exponential backoff?

1. It guaranteed that collision will not happen on next try

2. It decrease the chance of collision during next try

3. it increases congestion in the network

4. It decreases latency in of packets

Ans:It decrease the chance of collision during next try

10.What are the options that are true for channel access methods?

1. Token passing channel access methods provide better utilization of channel bandwidth under heavy load

2. Contention based channel access methods provide better flower transition latency under light load

3. Contention based channel access methods provide better (lower) transmission latency under heavy load

4. Token passing channel access methods provide better utilization of channel bandwidth under the load

Ans:Token passing channel access methods provide better utilization of channel bandwidth    

        under heavy load

        Contention based channel access methods provide better flower transition latency     

        under light load

Assignment 11

1.Which of the following TCP/IP protocols is used by a diskless machine to obtain its IP 

    address from a server?

1. RIP

2. RARP

3. RDP 

4. ARP

Ans:RARP

2.Which statement describes a spanning tree network that has converged?

1. All switch and bridge ports are either blocking or looping

2. All switch and bridge ports are in either the forwarding state or the blocking state. 

3. All switch and bridge ports are in the forwarding state.

4. All switch and bridge ports are assigned as either root or designated ports

Ans:All switch and bridge ports are in either the forwarding state or the blocking state.

3.Which is not detected for hidden stations in wireless LAN?

1. Signal

2. Collision

3. Frames

4. Data

Ans:Collision

4.How does the wireless LAN solve the hidden node problem?

1. By extending the antenna to different locations

2. By introducing RTS and CTS

3. By introducing random backoff

4. None of the above

Ans:By introducing RTS and CTS

5.A set that makes stationary or mobile wireless station and also have optional central base 

   station is known as

1. Extended service set

2. Network point set

3. Basic service set

4. Access point

Ans:Basic service set

6.The address resolution protocol (ARP) is used for

1. Finding the IP address of the default gateway.

2. Finding the IP address from the DNS.

3. Finding the MAC address that corresponds to an IP address

4. Finding the IP address that corresponds to a MAC address.

Ans:Finding the MAC address that corresponds to an IP address

7.Which component of ARP is responsible for sending a reply to the data link layer?

1. Input Module

2. Queue Controller

3. Cache Controller

4. Output Module

Ans:Input Module

8.Which of the following describes the function of RARP?

1. It is used to map a 32-bit IP address to a 48-bit ethernet address. 

2. It is used to map a 32-bit ethernet address to a 48-bit IP address

3. It is used to map a 48-bit ethernet address to a 32-bit IP address.

4. It is used to map a 48-bit IP address to a 32-bit ethernet address

Ans:It is used to map a 48-bit ethernet address to a 32-bit IP address

9.Which of the following is used to create a subnetting effect without explicitly declaring a 

   gateway?

1. Routing Table

2. ARP Table 

3. RARP Table

4. Cache Table

Ans:ARP Table

10.Which of the following is/are provided by VLAN?

1. Congestion control

2. Wireless communication

3. Time efficiency

4. Reduce network traffic

Ans:Time efficiency

Reduce network traffic

Assignment 12

1.Which of the following is/are true for Time Division multiple access (TDMA)?

1. Provides different frequency band to different data streams

2. Provides different code to different spreading code radios

3. Provides different time slot to different transmitters

4. None of them

Ans:Provides different time slot to different transmitters

2 What is the maximum magnitude bit rate in a noiseless channel if signal level L=2 and bandwidth=BW is used?

1. Half of BW

2. Same as BW

3. Double of BW 

4. None

Ans:Double of BW

3.What type of signal can be transmitted by Broadband?

1. Analog

2. Digital

3. Both Analog and Digital

4. None

Ans:Analog

4.Find the correct statement related to IP Security 

1. The transport mode protects the original IP header

2. The tunnel mode does not protect the original IP header 

3. The transport mode does not protect the original IP header

4. The tunnel mode protects the original IP header

Ans:The transport mode does not protect the original IP header

The tunnel mode protects the original IP header

5.What attack is used to make a computer resource unavailable?

1. Denial of service

2. Backdoors

3. Buffer overflows

4. Snooping

Ans:Denial of Service

6.What is the sequence for PCM?

1. Sampling,Encoding,Quantizing

2. Sampling,Quantizing,Encoding

3. Quantizing,Sampling,Encoding

4. Quantizing,Encoding,Sampling

Ans:Sampling,Quantizing,Encoding

7.Find the channel capacity if the SNR of a telephone line with bandwidth of 3000 Hz is 

    1023?

1. 3 Kbps

2. 3 bps 

3. 30 bps

4. 30 Kbps

Ans:30 Kbps

8.Find the security property if the data of a computer system can be modified only by 

   authorized parities.

1. Integrity 

2. Confidentiality

3. Authenticity 

4. Availability

Ans:Integrity

9.Which type of firewall is used to prevent direct TCP connection between the hosts?

1. Proxy Server

2. Circuit-level gateways

3. Packet filters

4. Application level gateways

Ans:Circuit-level gateways

10.Which of the following coding techniques is used to get the maximum synchronizing 

     capability?

1. Pseudoternary

2. Non Return to Zero Inverted (NRZI)

3. Manchester

4. Non Return to Zero-Level (NRZ-L)

Ans:Manchester