The author, in fact, has specifically written an article on the talk you mention: https://blog.cryptographyengineering.com/2016/08/13/is-apples-cloud-key-vault-

The author, in fact, has specifically written an article on the talk you mention: https://blog.cryptographyengineering.com/2016/08/13/is-apples-cloud-key-vault-crypto/ https://blog.cryptographyengineering.com/2016/08/13/is-apple.... Matthew Green is a capable cryptographer who engages with the wider security community and practical encryption a lot (e.g. https://blog.cryptographyengineering.com/2016/03/21/attack-of-week-apple-imessage/); https://blog.cryptographyengineering.com/2016/03/21/attack-o... if you're interested in this kind of thing, I'd recommend following him more closely (e.g. on Twitter.)