Joi Ito's Web

Joi Ito's conversation with the living web.

You know when you lose your connection and both sides frantically try to call each other back and cross paths? Richard Wolpert has a new rule:

  1. if you initiated the call and it drops you call the other person back.
  2. if you received the call and it drops you just wait for the call back.

Pass it on.


I am happy to see that these rules for mobile phones match what my parents told me in the 1970s when I was old enough to use the telephone.

Of course, with the power of the redial button on modern handsets it makes sense to relearn good habits from days gone by.

Just do it like Ethernet - then it doesn't matter if the other side of the call knows the rules. Use exponential backoff. Wait some short random time - call back. If busy: Wait a longer time - call back, etc.

Agreed! Happy to see this spreading...

Alt method: Continue speaking on the phone for several minutes, as if your friend was still on the line, then get startled when your phone rings and it's inexplicably the friend you thought you were talking to that very second.

This rule comes naturally to some of us.

This rule works good, iff conversation was really established and has been continuing for some time. Aber consider this: your friend calls your, you hear his unclear voice through noise and fade, fail to recognize any single word, and than connection drops. Are you sure he ever can do a second call? And if he can, would conditions be any better? In practice I use "ethernet rule", combined to "first caller rule" to decide the first delay: If I made call first, I recall immediately, if it was other party -- after near one minute. And then in both cases continue doubling the interval.

Nice rule. I was thinking the same as comment #3. I actually think about exponential backoff everytime I encounter that awkward social situation of bumping into someone and figuring out whether to go to their left, go to their right, or just stand still...

How about lawn watering rules: odd-numbered callers call back on Sunday and Thursday, even-numbered callers on Saturday and Wednesday, businesses on Monday and Friday, and just give up on Tuesday.

Yeah unfortunately this assumes a utopia where everyone knows The Rule, or you know for sure that the other party knows the rule. Perhaps establishing this at the start of a call by declaring "Caller calls back rule!" This has the added benefit of spreading said rule too.
(ack, I can't believe I am aiding the propagation of rules.)

This assumes you remember who initiated the call.

To me this rule is self-evident, but in rare cases you'll always experience that it is not. That's why it's good to write down such 'rules' in order to make them explicit. It is part of the social contract in the age of the machines. Geert

While we're at it, how about some rules on social kissing? We need some rules for that. Well, here in Britain anyway.

I use the exact opposite of this rule - many of my friends use prepay phone cards, and most calls drop because they're out of budget...

Hurray for utterly conflicting rules!

Alex: I've been in anumber of work-related calls that have gone on for so long a time, and been so stultifying, that they've burnt out whatever brain cells were used to flag who made the call....

No, no, no. This is not the way. Always the person who dropped the call should make the call back. The Scovill Protocol (what this is called) is very clear because you don't know how long the droppers going to be out of range (it could be short tunnel) or a long ride in an elevator.

Please stick to the Scovill Protocol - whoever dropped the call makes the call back. The droppee (is that a word?) waits.

And tell everyone so that we can clear it up. And dont worry about the case where both drop the call... very infrequent.