Quick hit on some things for reading up on control system security. One of my favorites is Kurtz, R., (2006) “Securing SCADA Systems” this particular book is older, but it has a great section on comparing ICS security protocols. Meant to be a text book it is very accessible to anybody with a light grasp of the technical issues.
A book I like, but it is not as well written in my opinion as Kurtz is this one by Knapp, Langill (2014) “Industrial Network Security, Second Edition: Securing Critical Infrastructure Networks for Smart Grid, SCADA, and Other Industrial Control Systems” The book is available on Kindle and I like how they updated it in version 2.0.
Finally a book that is not out yet, but I’m really looking forward to is the one by Bondugren, Singer, (PENDING) “Hacking Exposed Industrial Control Systems: ICS and SCADA Security Secrets & Solutions“. We’ll see when it comes out just how good the book is but I’m very hopeful.
There is a one stop place to find lots of introductory material on control systems. The US ICS-CERT recommendations for reading will let you get acquainted quickly. Most of the materials assume some type of mastery, but don’t let that dissuade you. The page has lots of good links to stuff that doesn’t cost. I’d start with the NIST documentation and recommended controls.
UPDATE:
Securing the smart grid by Flick and Morehouse is an interesting book. It is more about power generation than others out there. Also shows how the “grid” is really getting “smart” and the “dumb” grid really doesn’t exist anymore. Lots of security implications suggested.