OpenCBD: A Network-Encrypted Unknown Traffic Identification Scheme Based on Open-Set Recognition

Algorithm 2

Pretraining algorithm for network traffic model.

Input: unlabeled dataset , .

Output: pretrained model;

1: Fordo

2:  Extract the payload of , ;

3:  Fordo

4:   ;

5:   ;

6:   ;

7:  End for

8:  Ifthen

9:    (plaintext);

10:  Else

11:    (ciphertext);

12:  End if

13: End for

14: ;

15: ;

16: Randomly select consecutive 10-packet payload parts in to form , ;

17: Fordo

18:  ;

19:  ;

20:  Fordo

21:   Ifthen

22:    , where ;

23:   Else

24:    ;

25:   End if

26:   ;

27:   ;

28:  End for

29: End for

30: ;

31: ;

32: Return pretrained model.