I have read this article about the revelation that in 2010 major encryption mechanisms including big four (hotmail, facebook, google, yahoo) and other encryption mechanisms were broken by NSA and GCHQ.
The agencies have not yet cracked all encryption technologies, however, the documents suggest. Snowden appeared to confirm this during a live Q&A with Guardian readers in June. "Encryption works. Properly implemented strong crypto systems are one of the few things that you can rely on," he said before warning that NSA can frequently find ways around it as a result of weak security on the computers at either end of the communication.
and
For at least three years, one document says, GCHQ, almost certainly in close collaboration with the N.S.A., has been looking for ways into protected traffic of the most popular Internet companies: Google, Yahoo, Facebook and Microsoft’s Hotmail. By 2012, GCHQ had developed “new access opportunities” into Google’s systems, according to the document.
source:
http://www.nytimes.com/2013/09/06/us/nsa-foils-much-internet-encryption.html?hp&_r=0
http://www.theguardian.com/world/2013/sep/05/nsa-gchq-encryption-codes-security
My question is, what does Edward Snowden mean by Properly implemented strong crypto systems.
Could some IT security professional explain that to me a little more? What crypto systems does he think about?