Please make sure that you read this carefully before sending an email.
First, thank you for considering to work with me. I am always honored when I receive requests from prospective students who are thinking about working with me! However, before you contact me, you should read this:
I am a system security researcher. If you are interested in doing research in theory, networking, computer vision or any other computer discipline, I am not the right person for you. I am not interested, or active in these areas. Although we do use all sorts of different CS techniques (e.g., low-level programming, data science, machine learning) in our work, we are interested in solving security problems, and not interested in advancing the field in these areas. Please take a moment and look at some of the work we have done on the research page.
Being successful in this area requires a good systems background. Languages such as C, C++ should not be an issue for you. You should be able to develop web applications, you should be a proficient user of Linux / UNIX systems, and should be passionate about coding. Programming should not be a challenge for you, it should be a normal part of your life. Of course, if you don't enjoy coding, or if it is a big hurdle for you, then you are not a good fit for us...
When you apply, it is important for you to say why you want to do a Ph.D. and why you think you are qualified. Research is tough business, and you need to explain why you want to do it. You need to be self-motivated to do research. When you contact me, if I don't know anyone that you know (e.g., a former colleague), or you have not spent time in one of our sister labs, as the subject line, choose "Prospective student: [apply]". Also, in your email, tell me which three academic papers are your favorite, and explain to me in a paragraph why. These papers should not be my papers :).
If you are wondering whether you have the "minimal" technical skills to work in systems security, feel free to drop me an e-mail. I can give you access to a remote server, documentation, and some instructions, and you can see if you have the technical and intellectual skills... ;) We don't expect you to know everything, but we expect you to be able to read and learn. In your email to me, please include your ssh public key so I can give you remote access to the server. If you don't know what an ssh key is, I don't think you're a good fit, so another group would be better for you.