| There's a balance between keeping others out and preventing yourself being locked out. Every time you add another factor, you also have to add another recovery option in case you lose that factor: 1) Password(A) :| Hacker must break A :| Losing A locks you out 2) Password(A) + SMS recovery(B) :( Hacker must break A or B :) Losing A and B locks you out 3) Password(A) + SMS(B) 2FA :) Hacker must break A and B :( Losing A or B locks you out 4) Password(A) + SMS(B) 2FA + SMS password recovery(B) :| Hacker must break B :| Losing B locks you out 5) Password(A) + SMS(B) 2FA + SMS password recovery(B) +
Code sheet(C) :( Hacker must break B or (A and C) :) Losing B and (A or C) locks you out 6) Password(A) + SMS(B) 2FA + Code sheet(C) + 3rd channel password recovery(D) :) Hacker must break (A and (B or C)) or (D and (B or C)) :) Losing (A and D) or (B and C) locks you out Only the 6th option is unambiguously better than a single password. I guess using a friend's phone for password recovery and your own for 2FA would achieve that. |