Your word "easily" translates to "I haven't really thought hard about it and I am not an expert but it seems easy to me." That is a trap for beginners to crypt

Your word "easily" translates to "I haven't really thought hard about it and I am not an expert but it seems easy to me." That is a trap for beginners to cryptographic systems. Getting it right in all details is HARD, as has been proven time and again by failures. The theory is hard, the implementation is hard, and making it usable is hard.