Will a national alert system be ready for the next emergency?

Tuesday afternoon's 5.8 earthquake left hundreds of thousands of people along the East Coast temporarily without cell-phone service as circuits became overloaded and communications in many cases was reduced to texting or tweets. So what's a nation to do?

Tuesday afternoon’s 5.8 earthquake left hundreds of thousands of people along the East Coast temporarily without cell-phone service as circuits became overloaded and communication in many cases was reduced only to texting or tweets.

With a very strong Hurricane Irene approaching the Carolinas later this week, mobile telecommunications services again will be put to the test.

Will extensive and simultaneous cell-phone usage overload the system again?

Related coverage:

Social media travels faster than seismic waves

Where were you when the earthquake hit?

Rare 5.9 earthquake shakes up D.C. federal buildings

In all likelihood the answer is yes, but perhaps not for too much longer, according to Mark Titus, vice president of TeleCommunication Systems Inc., of Annapolis, Md., a provider of communication equipment and services that facilitate the transmission of voice, video and data.

During and after the quake cell-phone users were able to text message but not make voice calls because voice communication is transmitted over a dedicated voice channel and a point-to-point link first must be established for the call to go through, Titus said.

Voice takes up much more bandwidth than text messaging, which is carried on a data channel sent in packets, or digitized binary code, that do not require first establishing a link.

“The data channel more times than not is free and available. During times of emergencies people are trying to make a phone call all at the same time and there are finite resources within the cellular network,” he said.

He said investment in infrastructure to provide more capacity, including the upgrade from third generation, or 3G, to fourth generation, 4G, networks, will boost data speeds.

“Going forward the carriers are going to be offering voice services over 4G and over Long-Term Evolution, or LTE, networks,” he said, predicting that the new services will become available within 12 to 18 months.

“What you’re going to see going forward is more capacity for voice calls because voice calls over the 4G LTE networks are going to be like voice-over IP calls, like Skype,” Titus said.

Meanwhile, telecommunications companies in conjunction with FEMA are building the Commercial Mobile Alert Service (CMAS), which will alert all cell phones in a threatened area about the danger and what to do about it.

“One of the benefits of the Commercial Mobile Alert Service is that it is going to provide mass notification to a huge number of recipients without the network congestion,” he said. “And it does that because it uses a unique delivery technology called ‘cell broadcast.’”

Had the system been in place before the Aug. 23 earthquake, CMAS would have alerted every cell phone in the threatened area even if the phone owners were visitors and not local subscribers.

When CMAS is up and running, an alarm similar to the tone used by radio stations to test the emergency broadcast system will sound and a text message will inform the public.

“The real benefit of this service is, No. 1, it is going to be there as another form of communication. The majority of people now have cell phones so you’re not going to have to be in front of your TV. You’re also not going to have to have your NOAA weather radio on at night while you sleep because most people leave their cell phones on at night.”

A second benefit is that the service is going to be tied to a specific geographic area of interest so it will alert only those in the path of danger and provide instructions on how to cope and when the danger has passed, he added.

“Regardless whether you have a Droid phone or an iPhone or made by Nokia or whomever, the experience is going to be the same,” Titus explained.

“The very first version of this service is going to be limited to text only. And it’s going to be limited to 90-character messages, so these are going to be very short, concise messages that are going to inform the user that there’s an imminent threat and here’s what you need to do,” he said.

Titus said FEMA has a December timeframe for trials and an initial rollout that will cover the New York and Washington metropolitan areas.

“Ultimately the go-live production date across the country is in April 2012.” Titus said.