SK mobile network crash affects 5.6 million users for six hours

Nearly six million users of SK Telecom's mobile network were surprised this week when the network crashed and left them without service for about six hours.   This almost unthinkable occurrence was, of course, widely reported in the local press.   As noted by the Korea Joongang Daily, the crash did not occur because of hacking or some type of cyber attack.  Instead, as reported by the newspaper, it occurred "Thursday after a piece of equipment that verifies the locations of subscribers malfunctioned. The equipment, called Home Location Registration (HLR), is the main database of permanent subscriber information for a mobile network. The HLR was disrupted at a peak traffic time and could not distinguish SK Telecom users to transmit signals. According to the company, it only took 24 minutes to repair the equipment. But the blackout of services created a sudden rush of traffic as phone users tried to get back online, which overwhelmed the networks."