AT&T network rings dead

A major American phone system operator suffered from a dead network in more than 20 US states.
The AT&T Inc system failed for four hours last Tuesday preventing customers from making their usual voice calls over an internet connection.
An AT&T spokeswoman Mari Melguizo said: “The outage started at about 10.30am but the service was restored to most subscribers at 2.45pm. However the full extent of the outage is unknown.”
The network failure highlights possible problems with relying on Voice over Internet Protocol
A crashed server meant that the whole internet phoning system was rendered ineffectual.Customers who were trying to use AT&T’s U Verse VoIP phone service were greeted with no dial tone.
The problem was created by an IP network failure in the United States. There are an estimated 1.15 million AT&T U Verse Voice customers.