CPE 400 - Final Exam

In the transfer of file between server and client over four hops (links), if the transmission rates along the path is 40Mbps, 30Mbps, 20Mbps, 10Mbps, the throughput of the connection between server and client is a) 10Mbps b) 20Mbps c) 30Mbps d) 40Mbps

a) 10Mbps

How many bits are used by IPV6 for source or destination IP address? a) 128 bits b) 256 bits c) 512 bits d) 1024 bits

a) 128 bits

For an IP address 191.54.38.207 with netmask 255.255.0.0 and subnet mask 255.255.255.224 what is the number of hosts per subnet? a) 30 b) 62 c) 126 d) 254

a) 30

1 GBps is equivalent to a) 8Gbps b) 80 Gbps c) 54 MBps d) None of the above.

a) 8Gbps

In the layer hierarchy as the data packet moves from the upper to the lower layers, headers are a) Added b) Removed c) Rearranged d) Modified

a) Added

A set of rules that governs data communication is known as a) Protocols b) Standards c) RFCs d) None of the above

a) Protocols

BGP messages are encapsulated in _______. a) TCP segments b) UDP user datagrams c) IP datagrams d) none of the above

a) TCP segments

The special IP address 255.255.255.255 is used for _______ purpose. a) broadcasting b) multicasting c) unicasting d) booting-up

a) broadcasting

The domain name system is maintained by a) distributed database system b) a single server c) a single computer d) all of the above

a) distributed database system

TCP assigns a sequence number to each segment that is being sent. The sequence number for each segment is number of the __________ byte carried in that segment. a) first b) second c) middle d) last

a) first

In the congestion detection algorithm, if detection is by a time-out, a new _______ phase starts. a) slow start b) congestion avoidance c) congestion detection d) none of the above

a) slow start

Which protocol helps us in managing multicast groups? a. IGMP b. ICMP c. DNS d. ARP

a. IGMP

What is the mandatory header length of BGP packets? a) 32 bytes b) 19 bytes c) 7 bytes d) 1 byte

b) 19 bytes

If the ACK value is 200, then byte _______ has been received successfully. a) 200 b) 199 c) 201 d) None of the above

b) 199

How many bytes of mandatory header is used in IPV4 datagram? a) 4 bytes b) 20 bytes c) 32 bytes d) 16 bytes

b) 20 bytes

FTP server listens for connection on port number a) 20 b) 21 c) 22 d) 25

b) 21

By default, what type of query does nslookup do for a domain? a) MX b) A c) CNAME d) NX

b) A

Your home network router address is 192.168.2.1. Which class is this IP address in? a) B b) C c) D d) None of the above

b) C

Which of the following 5 components must be part of reliable data transfer protocol? a) Checksum, Timer, Congestion control, Acknowledgement and Pipelining b) Checksum, Timer, Sequence number, Acknowledgement and Pipelining c) Checksum, Sequence number, Congestion control, Flow control and Acknowledgement d) Timer, Sequence number, Congestion control, Flow control and Acknowledgement

b) Checksum, Timer, Sequence number, Acknowledgement and Pipelining

Which route computation algorithm is used by OSPF routing mechanism? a) Bellman-Ford b) Dijkstra c) DSR d) None of the above

b) Dijkstra

Distance vector routing algorithm is an example of a) Proactive Centralized routing algorithm b) Proactive Decentralized routing algorithm c) Reactive Centralized routing algorithm d) Reactive Decentralized routing algorithm

b) Proactive Decentralized routing algorithm

The transport layer protocol serving HTTP for web browsing is a) RTP b) TCP c) UDP d) all of the above

b) TCP

What does the phrase non-authoritative answer in the nslookup output mean? a) The information in the nslookup output is probably false b) The information in the output was obtained from a server cache c) The nslookup program is not finding any information at all d) The nslookup program cannot find a name server to query

b) The information in the output was obtained from a server cache

Multicasting communication is a) When a packet is sent from a single source to a single destination b) When a packet is sent from a single source to multiple destinations c) When a packet is sent from multiple sources to a single destination d) None of the above

b) When a packet is sent from a single source to multiple destinations

What is NOT true about persistent HTTP connection? a) multiple objects can be sent over single TCP connection between client, server b) downloading multiple objects must require multiple TCP connections c) Takes lesser time than non-persistent connection d) all of the above

b) downloading multiple objects must require multiple TCP connections

Bluetooth is an example of a) local area network b) personal area network c) virtual private network d) none of the above

b) personal area network

TCP is a(n) _______________ transport protocol. a) protocol delivery b) reliable c) best-effort delivery d) effortless delivery

b) reliable

In BGP, the _______ message is used by a router to withdraw destinations that have been advertised previously, or to announce a route to a new destination, or both. a) open b) update c) keep alive d) none of the above

b) update

Ethernet is a ________________________ protocol. a. Time division multiple access b. Random access c. Token ring d. Frequency division multiple access

b. Random access

What are the leading two bits in a class B IP address? a) 00 b) 01 c) 10 d) 11

c) 10

If a packet size is 1500 bits and the rate at which a router can pump out packets is 10 Mega bits per second, then the transmission delay is: a) 10 milliseconds b) 150 milliseconds c) 150 microseconds d) None of the above

c) 150 microseconds

How many bits are used for AS number field? a) 1 bit b) 8 bits c) 16 bits d) 64 bits

c) 16 bits

In RIP algorithm, if no advertisement heard from neighbor after ____ seconds, neighbor/link declared dead. a) 30 sec b) 60 sec c) 180 sec d) 360 sec

c) 180 sec

In a class C IP address, how many bits are used for network part and how many bits are used for host part? a. 12, 20 b. 20, 12 c. 24, 8 d. 28, 4

c) 24, 8

In TCP, the size of the transmission window is the ________ of rwnd and cwnd. a) Maximum b) Sum c) Minimum d) Subtraction difference

c) Minimum

The time required to examine the packet's header and determine where to direct the packet is part of a) Transmission delay b) Queuing delay c) Nodal Processing delay d) All of the above

c) Nodal Processing delay

For the following event at receiver, what would be TCP receiver's action? Event: arrival of out-of-order segment higher-than-expect seq. # . Gap detected. TCP receiver action: a) Delayed ACK. Wait up to 500ms for next segment. If no next segment, send ACK. b) Send cumulative ACK, ACKing both in-order segments, indicating seq. # of next expected byte. c) Send duplicate ACK, indicating seq. # of next expected byte. d) Do not take any action.

c) Send duplicate ACK, indicating seq. # of next expected byte.

Which one of the following protocol delivers/stores mail to receiver server? a) post office protocol b) internet mail access protocol c) simple mail transfer protocol d) file transfer protocol

c) simple mail transfer protocol

Which one of the following is NOT part of the network protocol stack? a) session layer b) application layer c) synchronization layer d) link layer

c) synchronization layer

Gigabit Ethernet has a data rate of ________Mbps. a. 10 b. 100 c. 1000 d. 10000

c. 1000

How many bits are there in a MAC address? a. 16 bits b. 32 bits c. 48 bits d. 128 bits

c. 48 bits

Assume a client is establishing communication with a server through a 3-way TCP handshake protocol. In this connection establishment phase, when the server is responding, which of the six flags (U, A, P, R, S, F) will be set by the server? a. U and A b. S c. A and S d. A and P

c. A and S

ARP requests and ARP replies are done using _________ and _________ communication mechanism. a. Unicasting; unicasting b. Unicasting; broadcasting c. Broadcasting; unicasting d. Broadcasting; broadcasting

c. Broadcasting; unicasting

A spanning tree is a graph in which there is no _____. a. Node b. Edge c. Cycle d. Root

c. Cycle

BGP can have two types of sessions: _______ and ________ sessions. a. E-BGP; A-BGP b. I-BGP; C-BGP c. E-BGP; I-BGP d. none of the above

c. E-BGP; I-BGP

10. [1] Convert the IP address from binary to dotted decimal notation: 01111111 . 11111111 . 11111111 . 11111111 a) 192.168.1.1 b) 255.255.255.255 c) 127.1.1.1 d) 127.255.255.255

d) 127.255.255.255

A source or destination port address in TCP segment is ________________ bits long. a) 48 b) 32 c) 24 d) 16

d) 16

For an IP address 191.54.38.207 with netmask 255.255.0.0 and subnet mask 255.255.255.224 what is the total number of subnets? a) 256 b) 512 c) 1024 d) 2048

d) 2048

In addition to assigning an IP address, what other information are provided by DHCP? a) Network mask b) First hop router information c) DNS server information d) All of the above

d) All of the above

Which of the following is NOT a correct statement? a) Router forwards packets b) Router has multiple IP addresses c) Routers build the backbone of the Internet d) Routers examine packets up to transport layer.

d) Routers examine packets up to transport layer.

NAT is controversial because a) NAT uses a forwarding table b) NAT obscures the inside of the network from the outside c) NAT reuses IP addresses d) Routers should only process up to layer 3 but NAT routers process up to layer 4

d) Routers should only process up to layer 3 but NAT routers process up to layer 4

UDP and TCP are both ____________ layer protocols. a) Application b) Session c) Presentation d) Transport

d) Transport

Application layer protocol defines: a) types of messages exchanged b) message format, syntax and semantics c) rules for when and how processes send and respond to messages d) all of the above

d) all of the above

DNS database contains a) name server records b) hostname-to-address records c) hostname aliases d) all of the above

d) all of the above

Network security is about: a) preventing unauthorized reading of information b) preventing unauthorized writing of information c) to make sure data is available in a timely manner when needed d) all of the above

d) all of the above

Which protocol helps us in resolving MAC address given the host's IP address? a. IGMP b. ICMP c. DNS d. ARP

d. ARP

Membership in a VLAN can be based on _________. a. Port numbers b. MAC addresses c. IP addresses d. All of the above

d. All of the above

DSR algorithm is an example of a. Proactive Centralized routing algorithm b. Proactive Decentralized routing algorithm c. Reactive Centralized routing algorithm d. Reactive Decentralized routing algorithm

d. Reactive Decentralized routing algorithm

Which of the following statements is correct? a. Bridge is used to connect networks using IP layer mechanism b. Hub has multiple separate collision domains c. Hub uses buffers d. Switch eliminates collisions

d. Switch eliminates collisions