# MS CryptoAPI RC4-1024 vs AES-128?

I'm trying to figure out MS CryptoAPI to generate a symmetric key on one computer then an RSA key on another, send over that public key to use to export the symmetric key to that other computer. I'm looking at their example here and it appears to create a session (symmetric) key of RC4 with a bit length of 1024 and then an RSA (AT_KEYEXCHANGE) of 1024 bits. Which then makes me wonder, how does RC4-1024 compare with AES-128? Or am I wrong on what that sample is actually doing?

MD5 based key derivation and RC4 encryption. Really? Example created in 2018? Microsoft should be ashamed of itself. I don't see that 1024 bit key, I see a 128 bit key created from the aforementioned MD5, and PKCS#1 RSA encryption. As for the key size "The sizes of a session key can be set when the key is generated. The key size, representing the length of the key modulus in bits, is set with the upper 16 bits of this parameter. Thus, if a 128-bit RC4 session key is to be generated, the value 0x00800000 is combined with any other dwFlags predefined value with a bitwise-OR operation."