Yup. Cliff Stoll. His first book is a great read. The second as well, but he caught a lot of flack for his 'Luddite' views. Personally, and with the aid of hindsight, I think he just undershot on his predictions.

I think so. It's also the one in which the protagonist stalled the attacker by means of a keyring, which is not so much a thing you can do any more.

That's the one. I remember reading it in 1991 or 1992, and just having my mind blinded by the whole story.