Reply To: What is a Porta cipher?

[madness]

OK, well, if you make a Q4 with these alphabet keys
AYCWEUGSIQKOMZBXDVFTHRJPLN NLPJRHTFVDXBZMOKQISGUEWCYA
and translate the shift key according to this table,
then encryption and decryption are the same as the Porta.

Porta, American      Porta, British       Q4
A,B                  A,B                  N
C,D                  Y,Z                  O
E,F                  W,X                  P
G,H                  U,V                  Q
I,J                  S,T                  R
K,L                  Q,R                  S
M,N                  O,P                  T
O,P                  M,N                  U
Q,R                  K,L                  V
S,T                  I,J                  W
U,V                  G,H                  X
W,X                  E,F                  Y
Y,Z                  C,D                  Z