In case you need reminding, wireless isn’t wireline.
Cellphone networks don’t have the resilience of wired networks, which almost never have a service disruption.
Rogers Communications subscribers found that out the hard way Wednesday when its Rogers and Fido wireless voice service across the country, along with some SMS service, died for a few hours.
By this morning service was completely restored. However no explanation has been offered yet as the cause of the outage.
In an interview Mark Goldberg, a Thornhill, Ont.-based telecommunications consultant, called the coast-to-coast failure “extremely unusual.”
There can be local problems – a cell tower gets knocked down – but a national problem is odd. The proof, he said is they are so rare.
Wireless networks can never have the availability of a wired network for the simple reason that a wireless carrier can’t control the conditions between the tower and a handset, he said. On a wired network the carrier controls everything right up to the business or home.
In addition, smart phones are mini-computers that run applications that can bring down the handset.
Still, Goldberg noted that both wireless and wired networks are designed with failover capability. He suspects that rather than a failure of a switch, a software glitch might be to blame for the national outage.
Carriers and their network equipment suppliers design the network to switch to backup systems under certain conditions. When there’s a failure, Goldberg said, post-event analysis often discovers a set of unanticipated conditions that cause a chain reaction to prevent the transfer.
On Thursday afternoon Rogers’ director of public affairs, Patricia Trott, said in an email the four and a half hour disruption was caused by “a software glitch on one of our switches,” which caused a surge on the network that transmits signals on how calls are managed. It was not due to a software upgrade. But the result was an overload on other mobile switches, which didn’t properly manage the spike, she said in an email.
The incident forced Rogers [TSX: RCI.A] CEO Nadir Mohamed to issue a statement apologizing to the roughly 10 million customers.
“I recognize this service interruption was unacceptable for our customers. We worked as quickly as possible to restore service and it was gradually restored over the course of the evening. I sincerely apologize to all of our customers for this significant inconvenience and appreciate their understanding and patience.”
“We’re continuing to investigate the root cause of the issue to help ensure it doesn’t happen again. To thank our customers for their patience, Rogers and Fido will proactively credit all of its postpaid wireless customers for one day of service.”
