In TCP communications there are 8 flags; FIN, SYN, RST, PSH, ACK, URG, ECE, CWR. These flags have decimal numbers assigned to them:
FIN = 1
SYN = 2
RST = 4
PSH = 8
ACK = 16
URG = 32
ECE = 64
CWR = 128
Jason is the security administrator of ASPEN Communications. He analyzes some traffic using Wireshark and has enabled the following filters.
What is Jason trying to accomplish here?
A.
SYN, FIN, URG and PSH
B.
SYN, SYN/ACK, ACK
C.
RST, PSH/URG, FIN
D.
ACK, ACK, SYN, URG
Explanation:
TCP.FLAGS==0x0x: In Decimal=2 –> SYN
TCP.FLAGS==0x12: In Decimal 2/16–> SYN/ACK
TCP.FLAGS==0x10:In Decimal 16–> ACK && ACK=1 && Not LEN———————————————->ACK
B