SSL/TLS: -
IOS provides APIs such as CFNetwork and SecureTransport so that developers can maintain a secure SSL, TLS networking session through details of implementation not open to public.
Airdrop Security: -
It allows users to share files on their iOS device. When a user enables AirDrop, a 2048 bit RSA identity and it's hash is created and stored on the device. When AirDrop is open, a signal is emitted through Bluetooth Low Energy such that nearby devices that also have AirDrop turned on can receive it. After the sender chooses to whom he/she wants to send, a TLS connection is created between the sender and the receiver, with iCloud identity certificates being exchanged. After the receiver accepts the files to transfer, the transmission begins.
FaceTime Security: -
It is used to do video calls on iOS devices with others using FaceTime. It establishes end to end connection between users using a Session Initiation Protocol. The contents of communication are encrypted and only the sender and receiver can decrypt them.
ICloud Security: -
Icloud stores contacts, photos, calendar, and other documents and synchronizes them on all of user's iOS devices. IOS keychain synchronizes all user's passwords on different iOS devices.
Files stored on iCloud are broken down into blocks and encrypted using AES-128 and key is derived from SHA-256 hash of it's block contents.
Continuity and Handoff: -
Continuity and Handoff feature has been introduced in iPhone to be syncronized with iOS and OS X devices. With Continuity a user's MAC/iPAD that share the same Wifi network associated with his iPhone and can make and receive calls as user's iPhone. The audio received from iPhone associated through the iPAD/MAC using encryption established through APNs.
Handoff is similar to Continuity, two devices establishes a Bluetooth Low Energy 4.0 connection through APNs. Then each generates a 256 bit AES key. The key exchange are used to encrypt and authenticate messages sent through Bluetooth in GCM.
Study Material
Quiz