Participants underestimated the number of calls they had made by an average of about 20%, and overestimated call duration by 40%.

ECONOMIST: The Interphone study: Mobile madness | The

But Krewski said that overall people generally have a good ability to recall the number of phone calls reasonably accurately, and tend to overestimate call duration by about 40 percent.

CNN: Study fails to end debate on cancer, cell phone link

The connections at each end create a channel reserved for the duration of a call.

ECONOMIST: Internet telephony

And even if investigators intercept a Skype call by tapping a suspect's internet connection, its strong encryption means they are likely to be able to determine only the time and the duration of the call.

ECONOMIST: Internet wiretapping

Generous loan covenants give managers more flexibility to work through their debt, and lenders are keen to extend the duration of loans rather than call them in and face more write-downs.

ECONOMIST: The buy-out barons say the worst is over. They would

That means that when a call begins, the network essentially opens a path of communication for the duration of the session between the users.

WSJ: U.S. Wireless Carriers Move to New Technology��For Voice