The top three mobile operators rolled out the much-awaited 4G service in the capital and some other major cities last evening -- within minutes of receiving the licence from the government.

Grameenphone, Robi, and Banglalink, which together account for more than 97 percent of the country's mobile subscribers' base, are offering the faster internet under their existing 3G data plans, much to the concern of customers.

They are worried that the volume-driven data plans would be exhausted faster than on 3G network, pushing up their consumption and monthly bill.

"Faster speed means faster consumption of bandwidth volume than before," said Shahjahan Mahmood, chairman of the Bangladesh Telecommunication Regulatory Commission, at the licence-giving ceremony last evening at the Dhaka Club.

But he hopes customers would be happy with the faster speed.

"Internet costs will not come down overnight and I hope it will happen gradually. We will look into the matter," he added.

The operators have informed the BTRC about their intent to sell the volume-driven data plans for 4G, like they are doing for 3G and 2G services, but they would ensure faster speed.

The per unit cost will definitely come down once a good number of customers start using the fastest data service, the operators said.

"The same has happened in case of 3G," said a senior executive of a top mobile operator.

The 4G technology is not likely to increase the per unit data price; rather it will lend itself to a better customer experience, said Mahmud Hossain, chief corporate affairs officer of Grameenphone.

Industry leaders and experts said they want speed-based packages instead of the volume-based ones as the operators buy speed from bandwidth companies.

"We want speed-driven packages as it will help ensure the service quality of mobile internet," said Syed Almas Kabir, president of the Bangladesh Association of Software and Information Services.

If customers get better service they can use the internet for their betterment and income-generating activities, which are not possible under 3G as the speed is poor outside of the capital, he added. The BTRC needs to be very clear and strict on service quality to meet the needs of the users after the launch of 4G, said Abu Saeed Khan, a senior fellow of LIRNEasia, a Colombo-based ICT think-tank.

The regulator should also not allow the operators volume-based packages in 4G as it is a fraudulent act.

 "I think the government is deeply involved with it as it approves the operators' volume-based packages, although the mobile operators are buying speed from bandwidth companies," said Khan, also a former secretary general of the Association of Mobile Telecom Operators of Bangladesh.

The BTRC is now finalising the integrated quality service regulations to maintain service standard.

As per the draft service quality directive, the regulator plans to set 7 megabits per second (Mbps) as the minimum speed for the 4G. The average speed for 3G is about 3 Mbps.

The operators did not immediately say anything about the speed of their 4G service.

4G will allow subscribers to enjoy high definition videos and other content.

Currently, Bangladesh consumes 550 Gbps of bandwidth and thanks to 4G, consumption will go up a few folds within the next couple of years.

Mustafa Jabbar, telecom minister; Shyam Sunder Sikder, telecom secretary; and the chief executive officers of the four mobile operators were present at the ceremony.