Data Communication

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Q & A
1In a _______ connection, more than two devices can share a single linkPoint-to-pointPrimaryMultipointSecondaryC
2Communication between a computer and a keyboard involves ______________transmissionCommunication between a computer and a keyboard involves ______________ transmissionHalf-duplexSimplexAutomaticC
3In a network with 25 computers, which topology would require the most extensive cabling?StarMeshBusRingB
4Which topology requires a central controller or hub?StarMeshBusRingA
5The _______ is the physical path over which a message travelsProtocolMediumSignalAll of the aboveB
6Which organization has authority over interstate and international commerce in the communications field?ITU-TIEEEISOFCCD
7The information to be communicated in a data communications system is the ________MediumProtocolTransmissionMessageD
8Frequency of failure and network recovery time after a failure are measures of the _______ of a networkPerformanceSecurityReliabilityFeasibilityC
9In _______ transmission, the channel capacity is shared by both communicating devices at all timesFull-duplexSimplexHalf-duplexHalf-SimplexA
10An unauthorized user is a network _______ issuePerformanceReliabilitySecurityAll of the aboveC
11Which topology requires a multipoint connection?MeshStarRingBusD
12A television broadcast is an example of _______ transmissionHalf-duplexFull-duplexSimplexAutomaticC
13A _______ connection provides a dedicated link between two devicesMultipointPoint-to-PointPrimarySecondaryB
14A cable break in a _______ topology stops all transmissionMeshStarPrimaryBusB
15The _______ layer changes bits into electromagnetic signalsPhysicalTransportNone of the aboveData linkA
16The physical layer is concerned with the transmission of _______ over the physical mediumProgramsProtocolsBitsDialogsC
17Mail services are available to network users through the _______ layerData linkPhysicalApplicationTransportC
18As the data packet moves from the lower to the upper layers, headers are _______AddedRearrangedModifiedSubtractedD
19As the data packet moves from the upper to the lower layers, headers are _______RemovedAddedRearrangedModifiedB
20The _______ layer lies between the network layer and the application layerData linkPhysicalTransportNone of the aboveC
21Layer 2 lies between the physical layer and the _______ layerData linkNetworkTransportNone of the aboveB
22When data are transmitted from device A to device B, the header from A's layer 4 is read by B's _______ layerApplicationPhysicalTransportNone of the aboveC
23Which layer functions as a liaison between user support layers and network support layers?Network layerTransport layerPhysical layerApplication layerB
24What is the main function of the transport layer?Process-to-process deliveryNode-to-node deliverySynchronizationUpdating and maintenance of routing tablesA
25Which of the following is an application layer service?Remote log-inFile transfer and accessMail serviceAll the aboveD