Apple Private Relay: Is TOR going mainstream?

Apple has announced (see here) a new iCloud premium feature called iCloud Private Relay:

when browsing with Safari, Private Relay ensures all traffic leaving a user’s device is encrypted, so no one between the user and the website they are visiting can access and read it, not even Apple or the user’s network provider. All the user’s requests are then sent through two separate internet relays. The first assigns the user an anonymous IP address that maps to their region but not their actual location. The second decrypts the web address they want to visit and forwards them to their destination. This separation of information protects the user’s privacy because no single entity can identify both who a user is and which sites they visit.

More information can be found for example here and here.

This seems very much a form of Onion Routing, which is all the theory and practice of TOR (The Onion Router, indeed). It will be very interesting to see how it will work out because there is the possibility of becoming a disruptive technology to improve the privacy and security of all of us when browsing the Internet.  

Cryptography for a COVID-19 Contact Tracing App by Apple and Google

Apple and Google (in alphabetic order) have released a draft of a cryptographic protocol named Contact Tracing (here the specification) for a new Privacy-preserving Bluetooth protocol to support COVID-19 Contact Tracing. As far as I understand (please correct me if I have misunderstood something), it should work as follows:

  • Bluetooth LE is extended on the devices with this new procotol
  • A service provider distributes an App which makes use of the protocol and communicates with a server managed by the service provider or a third party
  • Users install the App on their devices and keep Bluetooth on
  • When two devices with the App installed are nearby, they exchange some locally generated cryptographic key material called Rolling Proximity Identifier: these identifiers are privacy preserving, that is from the identifier alone it is not possible to identify the device which originated it; all Rolling Proximity Identifiers are stored only locally on the devices themselves (both originator and receiver)
  • When a user tests positive to COVID-19, she or he inserts this information in the App which then generates a set of cryptographic key material called Diagnosis Keys corresponding to the days in which the users could have been already infected; the App then sends the Diagnosis Keys to the server which distributes them to all other devices on which the App is running
  • When an App receives from the server some Diagnosis Keys, it is able to compute a set of Rolling Proximity Identifiers and to check if at least one is present in the local storage; if there is a match, the information derived is that on a certain day, in a 10 minutes time interval, the user of the App has been in proximity with a person who later tested positive to COVID-19.

Obviously a Privacy pre-requisite to all this is that neither server nor App manage or store any other information or metadata about the users and the devices on which the App runs.

Privacy and VPN Routers for Personal Security

Though I do not have one nor I tried one, Privacy and VPN routers like InvizBox, Anonabox, NordVPN, TorGuard VPN, and many others from well known brands (see here for example for a review), are becoming more common, easy to use also when travelling, and features loaded.

They typically allow to easily create private or commercial VPNs, establish Tor circuits and implement privacy filters on internet traffic. They are probably not as tight as Tails, but I expect that they are user friendly. 

Though I never felt the need of a commercial VPN service, I would consider using a security and privacy internet router which I can carry with me and easily activate even when travelling.