You can enable this protocol when you need to pair your phone with another user's phone. Because manual exchange is difficult.
Now I don't understand what problem you are trying to solve. If the two phones are physically close to each other, we have existing short-range data exchange systems such as infrared and Bluetooth that work fine. If the two parties already know each other, there is presumably some existing communication path such as e-mail they can use to exchange credentials.
On the other hand, if you are trying to solve the introduction problem, how to establish a channel between two people who don't already know each other, that's a famous swamp, and taking a couple of phones into the swamp doesn't change the issues.
Regards, John Levine, johnl@xxxxxxxx, Primary Perpetrator of "The Internet for Dummies", Information Superhighwayman wanna-be, http://www.johnlevine.com, ex-Mayor "More Wiener schnitzel, please", said Tom, revealingly. _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf