ender is sent a segment with destination port#80 via a TCP to a receiver that does not If a s support this port (it has a port 21); A) What will the receiver do (think about the TCP response message) in this case? B) What about UDP, does UDP reply back, if yes, how? ae is D repease: on.con ail Jo.co ype, which of the folloing is the right ope the last filed is DNS A) Type NS B) Type A C) Type CNAME D) Type MX E) None of these choices 1.9 When establishing a TCP server is said to be piggybacked, because it's A) a SYNACK segment. ) a special segment set its SYN bit to 1. C) a special segment set its SYN bit to 0 D) an acknowledement segment carrying payload connection, the third TCP segment sent by the client to the 1.10 TCP uses the following meckanism for increasing the congestion window size (ewnd): A) Additive increase additive decrease B) Additive increase multiplicative decrease C) Multiplicative increase additive decrease D) Multiplicative increase multiplicative decrease E) None of these choices 1.11 In Congestion Control when a 3-duplicate acknowledgment occur will set the new threshold (ssthresh) A) congestion window/2 B) old threshold/2 C) unchanged D) 1 MSS TCP Reno algorithm 1.12 Upon receipt of an errored segment, UDP A) It does flow control B) It does error control and recovery C) Retransmission D) It does not do flow control or error recovery 1.13 Self-scaling in TCP congestion control means that the size of the congestion window (ewnd) changes based on the acknowledgment arrival rate. A) True B) False L.14 Transport layer is designed to provide services to the Network layer. A) True B) False 1.15 A Round-trip of packet atl sent to router a+1 always longer than the round-trip delay of packet n sent to router n. A) True B) False Use Selective Repeat mechanism to show the ddlivery of S segnments from the sealar and dhe receiver? Notc: Segment 1 (SI) is already sent. You need to show the send and ack messages until all segments are delivered acks Assume: 1. Timeout 3 seconds 3. Sender Window N-4 2 S2 is dropped in the first try Sender Recelver Figure I: Selective Repeat Good luc L.1 A spltter in DSt. access setwork plis data and telephone signals ariving to thc home and forwarding the data to A) The company Digital Subscriber Line Access Maltiplexer (DSLAM B) The Internet C) The DSL modem D) The end system. 1.2 Which of the following options show the correct name for a packet of information in each layer? Aj Application layer frame, Transport layer. segment, Network layer datagram, Link layer message B) Application layer message, Transport layer: frame, Network layer datagram, Link layer. segment C) Application layer message, Transport layer: segment, Network layer datagram, Link layer frame D) None of these choices 1.3 Suppose users share a 2 Mbps link, also suppose each user required 200 kbps when transmitting. When circuit switching is used, number of users can be supported isusers A) 5 B) 10 C) 15 D) 20 1.4 The ability to inject packets into the Internet with a false source address is known as A) IP spoofing B) IP sniffing C) IP phishing D) Man-in-the-middle attack E) None of these choices 5 In HTTP pipelining A) multiple HTTP requests are sent on a single TCP connection without waiting for the corresponding responses B) multiple HTTP requests cannot be sent on a single TCP connection C) multiple HTTP requests are sent in a queue on a single TCP connection D) none of the mentioned 1.6 This is a time-sensitive service A) File transfer B) File download C) E-mail D) Internet telephony 1.7 The conditional GET mechanism A) Imposes conditions on the objects to be requested B) Limits the number of response from a server C) Helps to keep a cache up-to-date D) None of the above Question 9 .4) A) Describe the function (the use) ofthe "Head lengih" filed in the TCP header, and how does a differ from the "Length" filed found in the UDP header
