I am looking for an algorithm/procedure that encrypts a text where the alphanumeric data is encrypted into password-protected alphanumeric data.
I have seen other algorithms where a text like "Hello, How are you?" will be encrypted into something like this:
This is not what I am after.
I am looking for something that does this: "Hello, How are you?" will be encrypted into "Kjehh, Jey uwh wmd?"
Any idea how to do that?