Packt Publishing's Moodle Security (https://www.packtpub.com/toc/moodle-security-table-contents) addresses concerns of both administrators and users. The book provides information that can be helpful in addressing the very real legal liabilities that occur with security breaches.
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The organization of the book is easy to follow, and screen shots allow the user to work through the processes in a step-by-step way, and it allows both Linux and Windows users to implement security protocols for Moodle.
The first several chapters have to do with securing Linux and Windows servers. The chapters that deal with authentication, roles, and permissions include a variety of configurations, that include installation procedures.
On the side of user authentication and content assurance, the chapters are thorough and clear. Some current and ever-evolving threats -- bots, viruses, and other types of vulnerabilities are dealt with on a conceptual level as well as with step-by-step instructions.
One area that could be expanded in the Moodle Security is the underlying approach to computer forensics and historical approaches to determining crime / criminal elements.
Note: This title and other Moodle titles are available at a discount through the publisher for a limited time. (Moodle March campaign).