VNBusinessNews – Many mobile subscribers have lost money because of spam text messages (SMS) but service providers haven’t taken measures to protect their clients yet.

Mobile subscribers have recently been receiving a lot of spam SMS advertising different kinds of services, including fortune-telling services. Calling the phone numbers that deliver these messages, there is never an answer.

The Director of Viettel Telecom, Hoang Son, said there will be no replies to calls to these phone numbers because they are only used to deliver SMS.

It is said that thanks to promotion campaigns of mobile networks, many people bought SIMs with a lot of promotional money in the accounts. They used these SIMs to send SMS advertising some digital content services to earn commission. However, digital content service providers said they didn’t know about these phone numbers.

Representatives of Viettel and MobiFone said they have cooperated with some digital content service providers. However, digital content service providers are not allowed to send advertising SMS to subscribers from numbers with code 8x, which are the switchboard numbers of digital content service providers.

If subscribers receive spam SMS from numbers with the code of 8x, they can report to network operators. If spam text messages are sent from other numbers, mobile service providers can do virtually nothing, Hoang Son said, unless receivers complain to the network operator.

Spam text messages often advertise and lure mobile subscribers to use digital content services, without declaring service charges. Subscribers only know how much they have to pay after they have used the services.

MobiFone’s PR Manager, Tran Thuy Hanh, said that clients should protect themselves. If they don’t want to be bothered by spam SMS, they can put phone numbers that send advertising text messages to their phones on a blacklist (for modern mobile phones) or install blacklist software onto their cell phones.

Viettel’s Son said clients can register for a call-blocking service to prevent spam SMS.

How do senders of spam text messages get the phone numbers of subscribers? MobiFone’s Tran Thuy Hanh and Viettel’s Hoang Son said they never supply phone numbers or personal information of subscribers to digital content service providers.

Yet, spam SMS senders can easily get phone numbers by purchasing them from some sources, such as businesses which have their customers’ phone numbers. They can also randomly send messages to numbers. (BD)