●The TCP protocolis a (71) layer protocol. Each connection connects two TCPs that may be just one physical network apart or located on opposite sides ofthe globe. In other words, each connection creates a (72) witha length that may be totally different from another path created by another connection. This means that TCP cannot use the same retransmission time for all connections. Selecting afixed retransnussion time for all connections can result in serious consequences. Ifthe retransmission time does not allow enough time for a (73) to reach the destination and an acknowledgment to reach the source, it can result in retransmission of segments that are still on the way. Conversely, if the retransnussion time is longer than necessary for a short path, it may result in delay for the application programs.Even for one single connection, the retransmission time should not be fixed.A connection may be able to send segments and receive (74)faster during nontraffic period than during congested periods. TCP uses the dynamic retransmission time,a transmission time is different for each connection and which may be changed during the same connection. Retransmission time can be made(75) by basing it on the round-trip time (RTT). Several formulas are used for this purpose.(71) A.physicalB.networkC.transportD.application(72) A.pathB.windowC.responseD.process(73) A.processB.segmentC.programD.user(74) A.connectionsB.requestsC.acknowledgmentsD.datagrams(75) A.longB.shortC.fixedD.dynamic

●The TCP protocolis a (71) layer protocol. Each connection connects two TCPs that may be just one physical network apart or located on opposite sides ofthe globe. In other words, each connection creates a (72) witha length that may be totally different from another path created by another connection. This means that TCP cannot use the same retransmission time for all connections. Selecting afixed retransnussion time for all connections can result in serious consequences. Ifthe retransmission time does not allow enough time for a (73) to reach the destination and an acknowledgment to reach the source, it can result in retransmission of segments that are still on the way. Conversely, if the retransnussion time is longer than necessary for a short path, it may result in delay for the application programs.

Even for one single connection, the retransmission time should not be fixed.A connection may be able to send segments and receive (74)faster during nontraffic period than during congested periods. TCP uses the dynamic retransmission time,a transmission time is different for each connection and which may be changed during the same connection. Retransmission time can be made(75) by basing it on the round-trip time (RTT). Several formulas are used for this purpose.

(71) A.physical

B.network

C.transport

D.application

(72) A.path

B.window

C.response

D.process

(73) A.process

B.segment

C.program

D.user

(74) A.connections

B.requests

C.acknowledgments

D.datagrams

(75) A.long

B.short

C.fixed

D.dynamic


相关考题:

TCP71用()软件编程。

● A glue that holds the whole Internet together is the network layer protocol,(71). Unlike most older network layer protocols, it was designed from the beginning with internetworking in mind. Its job is to provide a -(72) way to transport datagrams from source to destination, without regard to whether these machines are on the same network or whether there are other networks in between them.Communication in the Internet works as follows. The (73)layer takes data streams and breaks them up into datagrams. Each datagram is transmitted through the Internet, possibly being fragmented into smaller units as it goes. When all the pieces finally get to the destination machine, they are reassembled by the(74) layer into the original datagram. This datagram is then handed to the transport layer, which inserts it into the receiving process' input stream.An IP datagram consists of a header part and a text part. The header has a (75) part and a variable length optional part.(71) A. IP (Internet Protocol)B. IP (Interworking Protocol)C. TCP (Transport Control Protocol)D. TCP (Transfer Communication Protocol)(72) A. best-qualityB. quality-guaranteedC. connection-orientedD. best-efforts(73) A. data linkB. transportC. networkD. application(74) A. data linkB. transportC. networkD. application(75) A. 40-byte fixedB. 64-byte fixedC. 20~64 bytes variableD. 20-byte fixed

以下程序段的输出结果为 ( )int j=2;switch(j){case 2:System.out.print("two.");case 2+1:System.out.println("three.");breakdefault:System.out.println("value is"+j);break;}A.two.three.B.two.C.three.D.value is 2

A host computer has been correctly configured with a static IP address, but the default gateway is incorrectly set. Which layer of the OSI model will be first affected by this configuration error?A. Layer 1B. Layer 2C. Layer 3D. Layer 4E. Layer 5F. Layer 6E. Layer 7

Acknowledgements, sequencing, and flow control are functions that are handled by which layer of the OSI model?A. Layer 5B. Layer 4C. Layer 7D. Layer 6E. Layer 3F. Layer 2G. Layer 1

● TCP/IP communication protocol contains four layers. From bottom to top, the four layers are __(71)__.(71)A.network interface layer, internet layer, transport layer and application layerB.internet layer, network interface layer, transport layer and application layerC.network interface layer, transport layer, network interface layer and application layerD.application layer, transport layer, internet layer and network interface layer

以下程序段的输出结果为( )。 int j=2 switch (j){ Case 2: system.out.print("two."): Case 2+1: System.out.println("three."); break: default: System.out.println (“value is”+j): Break }A.B.twoA.two.three.B.twoC.threeD.value is 2

Acknowldgement, Sequencing, and Flow control are characteristics of which OSI layer?() A. Layer 2B. Layer 3C. Layer 4D. Layer 5E. Layer 6F. Layer 7

All three types of cryptography schemes have unique function mapping to specific.For example,the synunetric key(71)approach is typically used for theencryption of data providmg(72),whereas asymmetric key cryptography is maidy used in key(73)and noruepudiation,thereby providing confidentiality and authentication.The hash(74)(noncryptic),on the other hand,does not provide confidentiality but provides messageintegrity,and cryptographic hash algorithms provide message(75)and identity of peers during transport over insecure channels.请作答72题。A.ConductionB.confidenceC.confidentialityD.connection

All three types of cryptography schemes have unique function mapping to specific.For example, the symmetric key approach (71) is typically used for the encryption of data providing(72), whereas asymmetric key cryptography is maidy used in key(73)and nonrepudiation, thereby providing confidentiality and authentication. The hash(74)(noncryptic), on the other hand, does not provide confidentiality but provides message integrity, and cryptographic hash algorithms provide message(75)and identity of peers during transport over insecure channels.A.Conduction B.confidence C.confidentiality D.connection