Technically you can take the Net + without having taken / passed the A+. However it might be good to take the A+ first. Good test practice to warm up for the Net + so that you get used to testing in that manner, just an idea. It is the usual (not always, the usual) way to do it: take the A+ then the Net +.
Sorry to be misleading but I had ment, I have two books, one A+ and one Network+, sometimes I take a break from the A+ book for a couple hours but feel like learning something else.
Would it be bad to jump into the Network+ book for those couple hours, so that way I can kill 2 birds with one stone?
Or do I need to know A+ essentials (no pun intended) before I even bother taking a look at a Network+ book?
It is not a requirement and from what i've read they really don't overlap. Sure there are some hardware overlaps like wiring types but no, you can go back and forth as long as you can remember that stuff.
As Wafflehammer said, new A+ is coming out in august which would mean the A+ exam you are studying for will be outdated soon, may be worth while just to hammer down on the Net+, pass it, then purchase a new A+ book and take that.
It wouldn't hurt though to read them while you wait, I mean, some of the stuff discussed in the "old" books will still be on the exam. Then when the new books come out you can skip through stuff you already know. Just something to do while you're waiting...can't hurt, that's what I am doing.
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