Is there an RC4 key that leaves the S array unchanged?

[chota]

hi,

I had a question regarding the rc4 stream cipher. I understand it is a bunch of permutations to the initial Array that goes from 0 to 255 with respect to the key.

However is there such a key such that after the permutation S is still the same? (ie still goes from 0 to 255)?

Any help would be appreciated, thanks

 

[mgb_phys]

I don't know if it is explicitly prohibited but it wouldn't necessarily matter - a key of 1,2,3,4,5...255 is just as random as any other if you don't know if advance that it's the one you are using.