A Novel Device Identification Method Based on Passive Measurement

Algorithm 3

Process of judging servers behind NATs.

Input: : List of Serve Detected from Algorithm 1; : List of NAT Detected from

Algorithm 2; : List of Host Detected from Algorithm 2; : List of Data Flow

Recording;

Output: List of NATs with Servers behind them;

1:

2: for each in do//traverse through each record

3:for each in do//traverse through each NAT

4:if is src of and dst is in then// T -> T

5:Put src in list

6:if is dst of and src is in then// S -> T

7:if protocol is HTTP then

8:Put dst in list

9:if protocol is UDP and pattern is query then//query or answer

10:Put dst in list

11: return //N represent NATs with Servers behind them