On Wed, 01 Jan 2014 11:55:37 +0200, Saku Ytti said:
Is this legal? Can NSA walk in to US based company and legally coerce to install such backdoor?
Well, legal or not... we will probably never know exactly what was said, but apparently the NSA was able to convince/coerce many of the 800 pound telecom gorillas to install taps and backdoors at the server end.
If not, what is the incentive for private company to cooperate?
The same incentive that was used to enforce secrecy on National Security Letters for many years - play nice or you'll end up in an oublette, with a trial to (maybe) be held behind closed doors, where you won't see any of the evidence against you because it's classified. Remember, the US sprouted this "indefinite detention" concept a while back, and still hasn't backtracked on it, because of its enormous usefulness as a cudgel to deal with "enemies of the State".