Businesses and consumers have asked why no backup plans were in place after a fire at one of nine major SingTel Internet exchanges crippled essential services across the island for more than 24 hours.
Mr Benjamin Tan, managing director of Internet service provider SuperInternet, said that it is common for providers of critical services like banks and hospitals to buy backup services from Internet service providers (ISPs).
Such backup services divert Internet traffic to an alternative route should the main cables be cut off - as in the case of SingTel.
"When there is a prolonged disruption like this, you can safely say that either the banks and hospitals did not buy the backup service, or the ISP's contingency plans did not kick in," said Mr Tan.
DBS Bank said yesterday that it was working with SingTel to work out why the network contingency plan that it had signed up for did not function as expected for the 18 branches affected by the blaze.
The bank said it has duplicated several layers of critical systems to improve the network's reliability. This enabled the vast majority of its banking services to avoid any impact from the disruption.
A spokesman for M1 said that it will pursue OpenNet's lack of backup plans with the Infocomm Development Authority of Singapore.