The word is without a doubt job security. Job security is when you will likely not be fired or layer off. If a position has a lot of Job security, you probably can mess up without loosing your job. You may even have good benefits because the company want to keep employees. They are not looking to replace people. Sometimes Job security is given to people who are good a something - are productive - have a rare skill - or have a relationship (such as friendship) with a boss - have seniority (which means they have been their longer than others). So job security may not be (or never is) given to all the employees equally.

I checked the reference, and had to laugh. Yes, Jesse is correct in saying it's a misspelling in the text: it should read "job security". A yob is a thug; a troublemaker from a low-class background with no manners or style. So your literal interpretation is correct (though I wouldn't use "jerks"; that's too vague), and pretty funny.