Looking for book recommendation on WAN circuit technologies

[Darren Strunk]

I am looking for a book (or other resource) recommendation on beginner, nitty gritty, circuit-level WAN technology and terminology. Not looking for an architecture book, but something that will help me talk to WAN circuit service providers using terms like All 1s, demarc, loopback, CSU/DSU - the basics. Thanks!

[b.hsu]

There are several books to point out. I would better suggest you to go to http://safari.ciscopress.com and select WAN as your topic and search for a suitable book that will meet your necessity.