Journals for tutorials I've written a paper that describes a system (for encryption), showing step by step how the system was formed. It's not a system I invented. I analyze that system and compare it with similar systems. Novel aspects include new understandings of those systems and how they relate to one-another. Can I publish this paper in a journal?
You describe an existing system, analyze it, and compare it with similar systems. If any of that is novel, your work is publishable, otherwise, you might be able to publish your work as a tutorial.