What's a proper window size in RSA exponentiation? I want to use the window method for RSA modular exponentiation.
Because of Side Channel Attacks (SCA).
But I don`t know what a proper window size is.
Window Size (W) for many practical implementation of RSA Algorithm (like OpenSSL) is related to key length.for example in openSSL library for insecure 80 bits key, W is 4 or for insecure 320 bits key , W is 5 and for 1024 or 2048 bits key (length), W is 6.

note:Maximum of Window size in openSSL Library is "6"