The figure below shows the timing diagram for a TCP connection between Hosts A and B from the beginning to the end. First, we see the 3-way handshake. The client (Host A) combines 50 bytes of data with the last ACK of the 3-way handshake. The server (Host B) combines 100 bytes of data with the ACK packet sent back to the client. The client (Host A) closes the connection at this point which results in a FIN segment being sent to the server (Host B), which is combined with the ACK for the 100-byte data. After a little while, the server (Host B) closes the connection as well.Enter the numeric values for a, b, c, d, e and f in the spaces provided below. No explanation is necessary. 0.5 mark for each.

Describe the situation that causes TCP to move from the state FIN-WAIT-1 to CLOSINGGroup of answer choicesThe actively closing side has sent an acknowledgment to the other side's FIN.The side of the connection that is actively closing the connection has completed the handshake and is waiting to be certain no packets remain in the network.The passively closing side has sent an acknowledgment to the other side's FIN.The side of the connection that is actively closing the connection recieves a FIN from the other side before receiving the ACK of it's own FIN.The side of the connection that is actively closing the connection has sent a FIN.

Consider the figure below, where a TCP sender sends 8 TCP segments at t = 1, 2, 3, 4, 5, 6, 7, 8. Suppose the initial value of the sequence number is 0 and every segment sent to the receiver each contains 100 bytes. The delay between the sender and receiver is 5 time units, and so the first segment arrives at the receiver at t = 6. The ACKs sent by the receiver at t = 6, 7, 8, 10, 11, 12 are shown. The TCP segments (if any) sent by the sender at t = 11, 13, 15, 16, 17, 18 are not shown.The segment sent at t=4 is lost, as is the ACK segment sent at t=7.What is the sequence number of the segment sent at t=2? What is the ACK value carried in the receiver-to-sender ACK sent at t = 6? What is the ACK value carried in the receiver-to-sender ACK sent at t = 8? What is the ACK value carried in the receiver-to-sender ACK sent at t = 10?

1.Question 1What ordering of TCP flags make up the Three-Way Handshake?1 pointSYN, SYN/ACK, ACKFIN, FIN/ACK, ACKSYN, ACK, FINSYN, ACK, SYN, ACK2.Question 2Transport layer protocols, like TCP and UDP, introduce the concept of a port. How many bits are in a port field?1 point3281643.Question 3A device that blocks traffic that meets certain criteria is known as a ________.1 pointHubFirewallRouterSwitch4.Question 4Which TCP flag is used to make the listening program respond immediately?1 pointURGACKRSTPSH5.Question 5_________are identified as ports 49152 through 65535.1 pointUser portsEphemeral portsSocketsSystem ports

TCP SYN Flood attack uses the three-way handshake mechanism.1. An attacker at system A sends a SYN packet to victim at system B.2. System B sends a SYN/ACK packet to victim A.3. As a normal three-way handshake mechanism system A should send an ACK packet to system B, however, system A does not send an ACK packet to system B. In this case clientB is waiting for an ACK packet from client A.This status of client B is called _________________Select one:a. "full-open"b. "half-closed"c. "half open"d. "xmas-open"

Which segment is sent by the client to synchronize sequence numbers during the three-way handshaking process?ACK segmentSYN + ACK segmentFIN segmentSYN segment