I'm going to do Cisco Networking soon and my friend did it last year and failed said you need to learn Binary for networks and stuff and they make you do it. So yeah any effective tutorials of learning Binary?
Seeing as I don't know how much you already know, I'll post this to help grasp the basics.
www.youtube.com/watch?v=LpuPe81bc2w
After you've watched that, it's probably best to google until you're comfortable. After I'd suggest looking at something like 2's compliment and floating point.
I was lucky enough to be taught this at work a while ago, and I don't really have any websites to hand.
When you're comfortable with binary, it's probably worth looking at hex and maybe octal, they aren't that much harder than binary and could come in useful.