New Delhi, March 21 (IANS): A day after Reliance Jio lodged a complaint with the advertising watchdog against broadband tester Ookla declaring Airtel as the 'Fastest Mobile Network' in India, Ookla on Tuesday clarified that test was based on third and fourth quarter data of 2016.

A day earlier, Reliance Jio had lodged a complaint with the Advertising Standards Council of India (ASCI) against Ookla's testing. 

"Ookla named Airtel as the 'Fastest Mobile Network' in India based on data from Q3 and Q4 of 2016. When analysing markets, like India, we take many factors into consideration, including dual SIM devices, network technology, device types, and more," said Jamie Steven, COO, Speedtest by Ookla, in a statement.

"In addition to what the user sees on their mobile application as they take a test in real-time, we apply a rigorous methodology when aggregating the data which uses a variety of internal data sources that control for potential variability in the market," he said.

"We have taken dual SIM information into consideration and fully stand behind Airtel being named 'India's Fastest Mobile Network'," Steven said.

"The claim of Airtel that it is India's fastest network is false, misleading and incorrect. The claim is being made by Airtel acting in a mala fide manner in collusion with Ookla LLC, who profess to be experts in the domain space of testing mobile internet speed," stated the letter sent by Reliance Jio to the ASCI, the advertising watchdog on Monday.

"We are rather amused by the allegations being made against our campaign. We believe that this is a deliberate attempt to malign our brand and misguide customers through a campaign of misinformation, which is something we now come across on a regular basis, in particular, on social media platforms," said Rajiv Mathrani, Chief Brand Officer, Bharti Airtel, in a statement on Tuesday.

Newcomer Reliance Jio, which has over 100 million subscribers, has also separately served a legal notice to Ookla for what it has termed as its "flawed" test.

Jio told ASCI that Ookla -- which had dubbed Airtel as "Officially The Fastest Network" -- does not have any accreditation from the Indian government.

"Without prejudice to the above, in any event, the way the award is being projected misleads the public into believing that Airtel has the fastest network today, that is when the advertisements are being aired/published," the letter said.