【正文】 C Sequence numberD Check sum71. The MSS is typically set by first determining the length of the largest linklayer frame that can be sent by the local sending host (the socalled____), and then will fit into a single linklayer frame. A Maximum segment size (MSS)B MTUC Sequence numberD Check sum72. The MSS is the maximum amount of ____layer data in the segment, not the maximum size of the TCP segment including headers.A ApplicationB TransportC NetworkingD Link73. Which of the following field is not used for connection setup and teardown?A Sequence numberB TSTC SYND FIN 74. ____ is the byte stream number of first byte in the segment. A Sequence numberB ACK numberC Checksum D port number75. ____ is the byte sequence numbers of next byte expected from other side. A Sequence numberB ACK numberC Checksum D port number76. Because TCP only acknowledges bytes up to the first missing byte in the stream, TCP is said to provide ____ acknowledgements. A Cumulative B SelectiveC SingleD Negative77. Fast retransmit means in the case that ____ duplicate ACKs are received, the TCP sender resend segment before timer expires.A 3B 4C 5D 678. TCP____ means sender won’t overflow receiver’s buffer by transmitting too much, too fast. A Flow controlB Congestion controlC Reliable data transferD Connectionoriented service79. TCP provides flow control by having the sender maintain a variable called the ____. A Receive windowB Congestion windowC Sliding windowD buffer80. How does TCP sender perceive congestion? A TimeoutB 3 duplicate ACKsC Both A and BD None of above81. Transport protocols run in ____. A Servers B Clients C Routers D End systems82. Which of the following services is not provided by TCP? A Delay guarantees and bandwidth guaranteesB Reliable data transfers and flow controlsC Congestion controlsD Inorder data transfers83. Which service does UDP not provide? A multiplexing B demultiplexingC errordetection D errorcorrection84. There are three major events related to data transmission and retransmission in the TCP sender, which one is not in it? A data received from application above B demultiplexing segmentC timer timeout D ACK receipt85. Which of the following applications normally uses UDP services? A SMTP B Streaming multimedia C FTP D HTTP86. Which of the following about TCP connection is not correct? A It is a broadcast connectionB It is a pointtopoint connectionC It is a pipelined connectionD It is a full duplex connection87. The SYN segment is used for____. A TCP connection setupB TCP flow controlC TCP congestion controlD Closing a TCP connection88. Which service helps prevent the internet from entering a state of gridlock?A reliable data transfer B flow controlC congestion control D handshaking procedure89. The Internet’s _____is responsible for moving packets from one host to another. A application layer B transport layerC network layer D link layer90. In the following applications, which one is a bandwidthsensitive application? A Email B web application C realtime audio D file transfer91. In the following applications, which one uses UDP? A Email B web application C file transfer D DNS92. In the following four descriptions, which one is correct? A If one host’s transport layer uses TCP, then its network layer must use virtualcircuit network.B Datagram network provides connection serviceC The transportlayer connection service is implemented in the routerD The networklayer connection service is implemented in the router as well as in the end system.93. ____ is a speedingmatching servicematching the rate which the sender is sending against the rate at which the receiving application is reading.A congestion control B flow controlC slidingwindow control D variable control94. In the following four descriptions about RcvWindow, which one is correct? A The size of the TCP RcvWindow never changes throughout the duration of the connectionB The size of the TCP RcvWindow will change with the size of the TCP RcvBufferC The size of the TCP RcvWindow must be less than or equal to the size of the TCP RcvBufferD Suppose host A sends a file to host B over a TCP connection, the number of unacknowledged bytes that A sends cannot exceed the size of the size of the RcvWindow.95. There are 6 flag fields. Which one is to indicate that the receiver should pass the data to the upper layer immediately? A PSH