The labs focus on hands-on techniques. They enable you to use cryptographic APIs and learn cryptanalysis.
The lectures focus on concepts, principles, and the big-picture. This includes providing security services and or building secure network protocols.
The lecture notes (linked to from the Calendar) include assigned readings from the textbook and from selected articles. These are integral parts of the learning experience of this course.
You are strongly encouraged to contribute to these discussions. By simply framing an issue into a question, you help sharpen the learning focus for yourself and for others. And by answering a question or engaging in a discussion, you sharpen your ability to prove a point or assess one.