Cisco Call Manager Study

I've been taking some time the last few weeks to really understand the inner workings of VoIP and how it works within the Cisco world. The ISP I work for deals with a lot of VoIP issues, so much that I think it's best that I spend the next few months learning how calls flow and are routed. A co-worker gave me great study material for Cisco Call Manager and how it works as a whole for VoIP. Honestly I never would of thought I would of liked VoIP but I guess that was because I didn't know anything about it. I figure that after I wrap up these Call Manager study guides and get some more on the job experience I'll focus all my attention back on to the Routing and Switching side of things. From there I think I'll see what the CCVP is all about!