Milagro uses 'Pairing-Based Cryptography' to do better decentralization of trust. This concept was new to me, briefly it seems like it uses special constructs of elliptic curves to provide zero-knowledge proofs and Diffie-Hellman style key exchange.
So, instead of using CAs and certificates to prove identity, this system would use indnividual pairings for authorization and would end up being more decentralized.
With M-PIN that is a big part of this library, you can have signatures but also upgrade to full key agreement and PFS, with a standard protocol that has been around since 2002.
What I am unsure about is how the decentralization will work, especially compared to just having CAs cross-sign keys. Seems like you will always need to ultimately have some trust anchor somewhere? Or can have a Perspectives-like 'network notary' system?