TCP/IP and OSI

14:29:18.927970 eth0 > 0:0:0a:05:0e:03 0:14:59:66:aa:3e ip 142: 199.17.59.166.telnet >
66.188.165.185.1749: P 1:89(88) ack 0 win 5840 (DF) [tos 0x10]

4510 0080 7ffa 4000 4006 cf40 c711 3ba6
                42bc a5b9 0017 06d5 4a83 71bb cad9 2c07
                5018 16d0 a266 0000 4b65 726e 656c 2066
                696c 7465 722c 2070 726f 746f 636f 6c20
                414c 4c2c 2064 6174 6167 7261 6d20 7061
                636b 6574 2073 6f63 6b65 740d 0a74 6370
                6475 6d70 3a20 6c69 7374 656e 696e 6720
                6f6e 2061 6c6c 2064 6576 6963 6573 0d0a

7. What are the sizes of each of the three headers?
LLC = 14
IP = 20 (5 hex words * 32bits/word = 20 bytes)
TCP = 20 (5 hex words * 32 bits/word = 20 bytes)

8. What version of IP is being used?
4

10. What is the purpose of the TTL (time to live) field?
The purpose is to determine the length of time in # of hops that a packet will be "alive". The TTL in the presented packet is: 4a hex = 74 decimal