Can anyone explain how to read and understand row 1,2 and 3?
My understanding for row 1 is : If any inside packets want to go to outside via any source port to destination port number 80 using HTTP protocol. It is allowed.
Row 2, if any outside packets want to come in via source port number 80 to destination port number bigger than 1023 using Protocol HTTP. It is allowed
For Row 3, no matter, the action is not allowed.
Is my translation correct? Also, is it usual to have action in row 3 in real life?
Also, what is the importance of the ACK bit in the flag field? Is it to make sure the packet sent out or received?
Thirdly, wiki says no state is one of the advantage of Packet Filter. Why is no state being one of the drawbacks of Packet Filter?