1. What is the sequence number of the TCP SYN segment that is used to initiate the TCP connection between the client computer (your computer) and gaia.cs.umass.edu? What is it in the segment that identifies the segment as a SYN segment? 2. What is the sequence number of the SYN+ACK segment sent by gaia.cs.umass.edu to the client computer in reply to the SYN? What is the value of the Acknowledgement field in the SYN+ACK segment? How did gaia.cs.umass.edu determine that value? What is it in the segment that identifies the segment as a SYN+ACK segment? 3. What is the sequence number of the TCP segment containing the HTTP POST command? Note that in order to find the POST command, youll need to dig into the packet content field at the bottom of the Wireshark window, looking for a segment with a POST within its DATA field. 4.Consider the TCP segment containing the HTTP POST as the first segment in the TCP connection. What are the sequence numbers of the first six segments in the TCP connection (including the segment containing the HTTP POST)? At what time was each segment sent? When was the ACK packet for each segment received? Given the difference between when each TCP segment was sent, and when its acknowledgement packet was received (in

1. What is the sequence number of the TCP SYN segment that is used to initiate the TCP connection between the client computer (your computer) and gaia.cs.umass.edu? What is it in the segment that identifies the segment as a SYN segment? 2. What is the sequence number of the SYN+ACK segment sent by gaia.cs.umass.edu to the client computer in reply to the SYN? What is the value of the Acknowledgement field in the SYN+ACK segment? How did gaia.cs.umass.edu determine that value? What is it in the segment that identifies the segment as a SYN+ACK segment? 3. What is the sequence number of the TCP segment containing the HTTP POST command? Note that in order to find the POST command, youll need to dig into the packet content field at the bottom of the Wireshark window, looking for a segment with a POST within its DATA field. 4.Consider the TCP segment containing the HTTP POST as the first segment in the TCP connection. What are the sequence numbers of the first six segments in the TCP connection (including the segment containing the HTTP POST)? At what time was each segment sent? When was the ACK packet for each segment received? Given the difference between when each TCP segment was sent, and when its acknowledgement packet was received (in other words, the RTT value for each of the six segments). Export these segments.other words, the RTT value for each of the six segments). Export these segments.

other words, the RTT value for each of the six segments). Export these segments.

ip.addr128.119.245.12&& tcp No 443-60937 [FIN, ACK] 5eqs] ck-2 Win-235 Len-O TSval-1970485339 T5ecr-300617. 443 60938 [FIN, ACK] Sq-1 Ack 2 Win 235 Len-0 TSval-1970485338 TSecr-308617 443 60944 ACK) Seq-1 Ack-523 Win-30880 Len TSva-1978405343 TSecr:30B6 179-. 43 68944 [ACK] Seq 138 Ack 574 Win 30088 Len- TSval 1978405485 TSecr 38861. 443-60944 [FIN, ACK) 5eq=138 Ack:574 Win-30080 Len: TSval-1978426510 TSecr. 185 9.876179 60937-443 [ACK] Seq-2 Ack-2 Win56 Len-TSval-304617997 TSecr 1978405330 68937 . 443 FIN. ACKJ Seq-1 Ack-1 Win-2056 Len:0 TSval-300617974 TSecr-197839- 60938 443 [ACK] Seq 2 Ack 2 Win-2856 Len- TSval-383617993 TSecr-1978485330 60938443 [FIN, ACK) 5eq=1 Ack=1 Win-2056 Len-UTSval-300617974 T5ecr-197039.. 68939 88 [ACKI Seq 2 Ack 2 Win 2858 LenTSval 308617992 TSecr 1970485330 68939-4 1FTN, ACK) Seq-1 Ack-1 Win-2a58 Lensa TSvals]R0617974 TSecr-1978391." 60942 B ACK] Seq-1 Ack l Win 131712 Len TSval 380617992 TSecr-1978485329 68942 83 IACKI seq= 100485 Ack=1 Win=13 17 12 Len=1448 TSval:300618110 TSecr=19.. 68942 83 IACKI sec-101933 Ack-1 win-131712 Len-1448 TSval-300618110 TSecr-19.. 68942 88 [ACKI Seq-103381 Ack-1 Win-131712 Len-1448 TSval-300618110 TSecr-19. 68942 BA [ACK] Sen-184929 Ack-1 Win 131712 Len-1448 TSval 361811 TSecr-1.. 68942 88 [ACK Seq= 106277 Ack=1 Win=1317 12 Len=1448 TSva 300618110 TSec 12. 68942 8g [ACK! Sea: 10709 Ack=1 Win-13 1712 Len-1448 Tsva 1-300618032 TSecrs]97." 68942 88 [ACKI Seq-107725 Ack-1 Win 131712 Len-1448 TSval-300618118 TSecr 19.. 68942 8a [ACKI Sen-109173 Ack-1 Win 131712 Len-1448 TSval 30061811 TSecr-19. 68942 Ba [ACK] Sen-118621 Ack-1 Win 131712 Len-1448 TSval 30618111 TSecr-19.. 68942 88 [ACKI sea: 112869 Ack=1 Win=131712 Len=1448 TSval:300618111 TSecr=19 168 9.926627 168 9.926793 Frane 60: 74 bytes on wire {592 bits)' 74 bytes captured (592 bits; on interface Ethernet 11, Src: CiscoMer_aa:55:c3 (88:15:44 : aa : 55:4)' Dst: Apple-65 : ef : 75 [78:4f:43:65:ef:75) Internet Protacol Versian 4, Srr: 128.119.245.12, Dst: 18.3.236.116 Source Port: 443 Sequence number: relative sequence number) [Next sequence nunber: relative sequence nunber)1 Acknouledgnent nunber: 1 elative ack number) = Header Length: 4D bytes {10 Window size value: 28968 [Calculated window size: 28968] Checksum: 8xflfc [unverified Cherksum Status: Unverified Urgent pointer: 0ptions : (29 bytes, Maxmun segment size, 5ACK permitted, Tine stamps, No-Operation SNOP)' window scale [SEQ/ACK analysisl