Description : In an Ethernet local area network, which one of the following statements is TRUE ? a. A station stops to sense the channel once it starts transmitting a frame. b. The purpose ... collision is detected. d. The exponential backoff mechanism reduces the probability of collision on retransmissions
Last Answer : The exponential backoff mechanism reduces the probability of collision on retransmissions
Description : Inthe _________ method, a special packet called a ______ circulates through the ring. A) reservation: control frame B) polling: poll request C) token passing: token D) none of the above
Last Answer : token passing: token
Description : A _________ network is across between a circuit-switchednetworkand a datagram network. It has some characteristics ofboth. A) virtual-circuit B) packet-switched C) frame-switched D) none of the above
Last Answer : virtual-circui
Description : In _________, thereis no resource allocation for a packet. A) datagram switching B) circuit switching C) frame switching D) none of the above
Last Answer : datagram switching
Description : An IGMP packet is carried in an __________ packet. A) UDP B) IP C) Ethernet frame D) noneof the above
Last Answer : IP
Description : Which of the following statements is TRUE? a. Both Ethernet frame and IP packet include checksum fields b. Ethernet frame includes a checksum field and IP packet includes a CRC field c. Ethernet ... and IP packet includes a checksum field d. Both Ethernet frame and IP packet include CRC fields
Last Answer : Ethernet frame includes a CRC field and IP packet includes a checksum field
Description : When does the station B send a positive acknowledgement (ACK) to station A in Stop and Wait protocol? a. only when no error occurs at the transmission level b. when retransmission of old packet in a novel frame is necessary c. only when station B receives frame with errors d. all of the above
Last Answer : only when no error occurs at the transmission level
Description : Which of the following term describes PDU encapsulated at Transport Layer? a. Frame b. Packet c. Data d. Segment
Last Answer : d. Segment
Description : A network is a cross between a circuit-switched network and a datagram network. It has some characteristics of both. a. virtual-circuit b. packet-switched c. None of the Given d. frame-switched
Last Answer : a. virtual-circuit
Description : The purpose of the _______is to provide flow and error control for the upper-layer protocols that actually demand theseservices A) MAC B) LLC C) LLU D) none of the above
Last Answer : LLC
Description : _______is the rateof change with respect totime. A) Amplitude B) Time C) Frequency D) Voltage
Last Answer : Time
Description : A _______is the optical link connecting two neighbor devices. A) section B) line C) path D) none of the above
Last Answer : line
Description : In ATM,_______is for short packets. A) AAL1 B) AAL2 C) AAL3/4 D) AAL5
Last Answer : AAL2
Description : A _______is an ARP thatacts on behalf of a set of hosts. A) ARP B) RARP C) proxy ARP D) noneof the above
Last Answer : proxy ARP
Description : A _______is a data communicationsystem withina building, plant,or campus, orbetween nearby buildings. A) MAN B) LAN C) WAN D) none of the above
Last Answer : LAN
Description : A packet filtering firewall can a. deny certain users from accessing a service b. block worms and viruses from entering the network c. disallow some files from being accessed through FTP d. block some hosts from accessing the network
Last Answer : d. block some hosts from accessing the network
Description : An IP datagram of size 1000 bytes arrives at a router. The router has to forward this packet on a link whose MTU (maximum transmission unit) is 100 bytes. Assume that the size of the IP header is 20 bytes ... the IP datagram will be divided into for transmission is : a. 10 b. 50 c. 12 d. 13
Last Answer : d. 13
Description : Which of the following statement is incorrect? A. The Addresses Resolution Protocol, ARP, allows a host to find the physicaladdress ofa target host on the samephysical network, given only the target IP address. ... -addresses of our choice to every machine. D. All of theabove E. None of the above
Last Answer : All of theabove
Description : Which of the following statements is correct for the use of packet switching? A. the subdivision of information into individuallyaddressed packets in conjunction with alternativerouting arrangementenabled the transmission path ... capacity could be achieved. D. All of theabove E. None of the above
Description : A __________ is a device that forwards packets between networks by processing the routing information included in the packet. a) bridge b) firewall c) router d) hub
Last Answer : c) router
Description : A wooden block fixed on back side of a door frame on its post, is known as (A) Cleat (B) Stop (C) Horn (D) None of these
Last Answer : Answer: Option B
Description : ______ eliminates the varying delay times associated withdifferent-size packets. A) X.25 B) Frame Relay C) ATM D) all of theabove
Last Answer : ATM
Description : Which of the following technique isused for encapsulation? A. a technique used inbest-effort delivery systems toavoid endlessly loopingpackets. B. a technique used by protocols in which a lower level ... network that cannothandle the originaldatagram size D. All of theabove E. None of the above
Last Answer : a technique used by protocols in which a lower level protocol accepts a message from ahigher level protocol and places it in the data portion of the low level frame
Description : Which of the following technique isused for fragment? A. a technique used inbest-effort delivery systems toavoid endlessly loopingpackets B. a technique used by protocols in which a lower level protocol ... network that cannothandle the originaldatagram size D. All of theabove E. None of the above
Last Answer : one of the pieces that results when an IP gateway divides an IP datagram into smallerpieces for transmission acrossa network that cannothandle the originaldatagram size
Description : 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)
Last Answer : b. 2^(n-1)
Description : Suppose that the one-way propagation delay for a 100 Mbps Ethernet having 48-bit jamming signal is 1.04 micro-seconds. The minimum frame size in bits is: a. 112 b. 160 c. 208 d. 256
Last Answer : d. 256
Description : The minimum frame size required for a CSMA/CD based computer network running at 1 Gbps on a 200m cable with a link speed of 2 × 108m/s is a. 125 bytes b. 250 bytes c. 500 bytes d. None of these
Last Answer : b. 250 bytes
Description : 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 ... is lost, the sender throughput is __________ bytes/second. a. 2500 b. 2000 c. 1500 d. 500
Last Answer : a. 2500
Description : Consider a CSMA/CD network that transmits data at a rate of 100 Mbps (108 bits per second) over a 1 km (kilometre) cable with no repeaters. If the minimum frame size required for this network is 1250 bytes, what is the signal speed (km/sec) in the cable? a. 8000 b. 10000 c. 16000 d. 20000
Last Answer : d. 20000
Description : 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
Last Answer : c. 464
Description : In the Ethernet frame, the_______field contains error detection information. A) CRC B) preamble C) address D) none of the above
Last Answer : CRC
Description : ______ is the cell relay protocol designed by the corresponding Forum and adopted by the ITU-T. A) X.25 B) Frame Relay C) ATM D) none of the above
Description : What is used to see if a client is still connected to a NetWare server? A. Spoofing TCP/SAP B. Watchdog packet C. GNS Round Robin D. DNS Round Robin
Last Answer : Watchdog packet
Description : A local telephone network isan example of a_______ network. A) packet-switched B) circuit-switched C) message-switched D) none of the above
Last Answer : circuit-switched
Description : The _______ address in theheader ofa packet in adatagram network normally remains thesame during the entire journeyof the packet. A) source B) destination C) local D) none of the above
Last Answer : destination
Description : We cansay thata packet switchhas _______ typesof components. A) two B) three C) four D) none of the above
Last Answer : four
Description : Packet-switched networks can alsobe divided into ______subcategories: virtual-circuit networks and datagram networks A) four B) three C) two D) five
Last Answer : two
Description : The ATM data packet is acell composed of ______bytes. A) 40 B) 50 C) 52 D) 53
Last Answer : 53
Description : Which of the following is anecessary part of the IPv6 datagram? A) Base header B) Extension header C) Data packet from the upper layer D) (a) and (c)
Last Answer : Base header
Description : The IP packet that carries an IGMP packet has a value of _______ in its protocol field. A) 3 B) 2 C) 1 D) noneof the above
Last Answer : 2
Description : If the sender is a host and wants tosend a packet toanotherhost on another network, the logical address that must be mapped to a physical address is ______. A) thedestination IP address in the datagram ... the IP address of therouter found inthe routing table C) either a or b D) noneof the above
Last Answer : the IP address of therouter found inthe routing table
Description : f the sender is a host and wants tosend a packet toanotherhost on the samenetwork, the logical address that must be mapped to a physical address is ______. A) thedestination IP address in the datagram ... the IP address of therouter found inthe routing table C) either a or b D) noneof the above
Last Answer : hedestination IP address in the datagram header
Description : RPB guarantees that eachdestinationreceives _________ of the packet. A) one copy B) no copies C) multiplecopies D) none of the above
Last Answer : one copy
Description : RPF guarantees that eachnetwork receives only ____ of the multicast packet. A) one copy B) two copies C) a or b D) none of the above
Last Answer : none of the above
Description : In _______, the router may forwardthereceived packet through several of its interfaces. A) unicasting B) multicasting C) broadcasting D) none of the above
Last Answer : multicasting
Description : In ______, the router forwards thereceived packet through only one of its interfaces. A) unicasting B) multicasting C) broadcasting D) none of the above
Last Answer : unicasting
Description : The taskof moving the packet from theinput queue to the output queuein a router is done by_________. A) input and output ports B) routing processor C) switching fabrics D) none of the above
Last Answer : switching fabrics
Description : In _______delivery, the deliverer of theIP packet and the destination are on different networks. A) aconnection-oriented B) a direct C) an indirect D) none of the above
Last Answer : an indirect
Description : In _______delivery, both thedeliverer of the IP packet and the destination are on the same network. A) aconnectionless B) a direct C) an indirect D) none of the above
Last Answer : a direct