If you notice that sometimes when you sign on after you enter a site or post a comment or question you are asked to duplicate a "code" that appears for verification of who you are. This appears often if you type the wrong password once. It was devised to prevent robots from password testing or fake posting - usually putting up something political or an advertisement for Viagra or hair removal.
Trolling refers to human actions - people posting while in "troll" behavior modes - as in the troll that lives under the bridge. Posting "evil". I admit that sometimes I "troll" politically but mostly in political debate on politically inspired blogs and I go after Sarah Palin perhaps more than I should. I do hold the honor of being banned from Ann Coulter's blog for comments not in keeping with the spirit of her site. No kidding.The author of the Op-Ed is from Facebook - the current wide open door for trolling. The "safety" that Facebook says it builds in rests in having your own account and your own "wall" where you can invite or restrict your circle of friends to comment and interact. But Facebook, in order to be economically viable, survives on members expanding their circle of friends so advertising can be targeted not in ones and twos but in hundreds and thousands. It is really that simple - they have applied a method to congregate "like people". That also means you might get a "friend" back doored into your circle of friends who in turn will let in more etc. For this you can get trolled at one point.
The bigger problem is trolling by "anonymous" - sites that permit comments and postings by people who do not display a name (not robots) and are untraceable (no email registration or IP recording). Whew. Ok. So my position is that to post you should use an email that has its IP embedded in it (most if not all do unless disabled) and if you don't, you can't post.
I guess that's about it.