The latest version of Weave (now "Firefox Sync") also uses J-PAKE for exchanging keys between devices. http://en.wikipedia.org/wiki/Password_Authenticated_Key_

The latest version of Weave (now "Firefox Sync") also uses J-PAKE for exchanging keys between devices. http://en.wikipedia.org/wiki/Password_Authenticated_Key_Exchange_by_Juggling http://en.wikipedia.org/wiki/Password_Authenticated_Key_Exch... Earlier versions required you to type a 30-character encryption key on each device that you connect to your sync account. Since your encryption key is never sent to the sync server, you had to transfer it manually. Now you can do the same by exchanging a much shorter (12-character) code, with a UI similar to Bluetooth pairing.