They throw out the claim (~4:10) the facility in utah could store "about 100 years of the world's communications".
Has anyone done the math? How much could that facility store. If they were indeed recording word-for-word content, how many days/months/years could they store?
No, it's not "nobody knows for sure." If you do the right math and don't assume that they have the storage technology not available to the rest of the world (which is a reasonable assumption) it's obvious that the data storage in an accessible way inside that center has an upper bound of an order of around one exabyte (1e18) (a million terabytes). So it's even more probable that it's less, say 0.2 EB.
Now somebody here claims it's around 1e7 B compressed for an hour of phone talk (not transcribed only compressed). That gives 2e10 hours stored. Storing it for 2e8 Americans there's space for 100 hours per person. But they also want the world, not only Americans.
You seem very confident of your input parameters. What are you basing 0.2-1EB on? It seems like there is a lot unknown about the utah data center, so all their "expert estimates" sounded more like guesses. Hence my conclusion "nobody knows for sure".
Even if, as you say, the estimate is 100hours per person. How much time does the average person spend on the phone? My current cell plan has 200 minutes per month, and I never go over. Say the average person spends 1000 minutes (16.7 hours), that means you could store a month of rolling phone conversations, and be only at 16.7% capacity. That leaves a fair bit of extra room for persons of interest internationally.
Your estimate is correct, somewhere on HN I've read that average young American talks 20 hours per month, older somewhat less. You're also correct that as soon as they decide that not everybody is actually important, the capacity to store communications of "persons of interest" is enough for "the whole life of the persons of interest."
Regarding my estimates, somebody here on HN also sent a link to the highest capacity automated tape libraries, and using them instead of hard disks the estimation of capacity still fits in the same order of magnitude. I still assume hard disks are more convenient than tapes for anything that needs to be accessed "when needed" (who would accept to say "will get the data bout the terrorists regarding the attack tomorrow, but it will take two days." So I can even bet that the main storage there are hard disks.
Has anyone done the math? How much could that facility store. If they were indeed recording word-for-word content, how many days/months/years could they store?