DTAC’s third network collapse in three weeks

10 January 2012 |


A series of network failures led Thailand’s Total Access Communication (DTAC) to promise triple redundancy on critical network paths.

Three network outages, attributed variously to the migration of the Home Location Register (HLR) between two databases, a failed switch, a car accident and a bush fire, have plagued recent weeks for DTAC, the second largest mobile phone provider in Thailand.

The first incident on December 21 occurred when DTAC was moving its HLR as part of a two-year modernisation plan to replace its 18-year old 2G network so as to be ready for 3G or LTE. The Bangkok Post reported that the network collapsed for almost five hours, affecting 900,000 users in southern provinces plus another 900,000 in Bangkok.

Although DTAC claimed that this was largely due to to traffic congestion among mobile switching centres and base station controllers, this collapse has led to a temporary suspension of its migration plans. DTAC has paid out 300 million baht (€7.4 million) in compensation for the failure.

The second incident took place when a switch failed on January 5. The earlier difficulties with the HLR migration caused this minor incident to become a significant event, and caused DTAC to receive a fine of 50 million baht.

In a public apology at a press conference, chief executive Jon Eddy Abdullah has said that DTAC understands the technical issues behind these outages and he has ordered a doubling of the HLR database capacity before further migration takes place. This is expected to take six weeks.

To prove that bad things come in threes, earlier this week two redundant cables were severed during a car accident, shortly followed by a bush fire which cut the remaining cable. CEO Abdullah ruled out sabotage, saying, “There are easier ways to cut a fibre optic cable.” In an attempt to prevent such occurrences in the future, DTAC has announced that it will be building triple redundancy into critical network paths.

The outages have led Thailand’s National Broadcasting and Telecommunications Commission (NBTC) to announce a formal investigation into DTAC. NBTC’s vice-chairman Settapong Malisuwan has requested access to log files to see if the network crash was due to a technical issue or to negligence.

Commissioner Prawit Leesathapornwongsa has issued a statement that in the future DTAC must submit any plans for database migration to NBTC for approval six months in advance.