Well, for sure Airtel spends a lot of money on ads, stating that theirs net is the fastest. For that they even have a world famous annoying model ( please someone hit hard on her head with a blunt object)
We can relate Airtel net Speed to two things..
Early 90s dial up connections
The rotating, disturbing and depressing logo of Doordarshan
Well there is one thing Airtel is good at for sure... LYING