The protocol that AT&T subscribers use a minimum of five times per day when a call they are on is dropped. Of particular importance to iPhone 4.0 users.
It is common attiquette that upon realizing a call has been dropped, ONLY the original caller should attempt to re-establish the conversation, not the recipient of the original call. This is done so to avoid the situation where both callers repeatedly try to call one another only to be routed directly into each other's voicemail.
by Daylorb November 05, 2010