KOLKATA: The telecom regulator’s latest paper on deferring implementation of a zero-interconnect usage charges (IUC) regime has triggered a blame game among older operators Bharti Airtel and Vodafone Idea, and newest entrant Reliance Jio Infocomm. They blame each other for voice traffic imbalance.People familiar with matter at Airtel and Vodafone Idea (VIL), who asked not to be named, blamed the Mukesh Ambani-led telco for recently limiting the duration of rings for calls being made from its network to just 20 seconds – or just 4-5 rings – which triggers a call-back, aimed at ensuring a call terminates on Jio’s network, generating interconnect revenue for the telecom market leader.People familiar with the matter at Jio, though, accused rivals of keeping call rates exorbitant — with an effective outgo of almost Rs 2 per minute — for the lowest class of 2G users, forcing them to give missed calls to a Jio user to elicit a return call, ensuring the call terminates on incumbents’ networks, generating IUC revenue for them. Interconnect charge (IUC) is paid by call-originating telco to destination operator.A Vodafone Idea spokesman countered, saying “we offer choice to customers via affordable products across 2G, 3G and 4G technologies, wherein users can opt for plans that best meet their needs for voice and data services”.At press time, Jio and Airtel did not reply to ET’s queries.Trai, which some two years ago had reduced IUC by 57% to 6 paise a minute, and ordered the scrapping it from January 2020, has called for a review, saying consumers are yet to migrate completely to data calls and that the imbalance in voice traffic between operators still exists. Trai on Wednesday said the traffic imbalance in terms of absolute minutes between an only 4G operator (read: Jio) and other operators is still 40 billion minutes per month at June end, though its lower than the peak of around 60 billion minutes a month in December 2017.The move to data calls, it had earlier said, would have reduced the cost of generating a call, encouraging a sharp reduction in traffic imbalance, thus removing need for IUC. But that is yet to happen.A senior industry executive said Jio’s decision to cut maximum ring time for answering a call to just 20 seconds instead of the 40-45 seconds industry practice has “virtually converted outgoing calls from Jio’s network into missed calls, prompting many Airtel customers to call back Jio users, in turn, generating interconnect revenue for the new entrant.”“Jio’s action has resulted in losses of roughly Rs 80 lakh per day with an additional 132 million voice minutes of usage per day terminating on its network from Airtel’s,” said the person, added that IUC should be 14 paise a unit.Jio’s move, he said, was a clever ploy to rapidly "ring in symmetry in Jio’s incoming and outgoing off-net traffic” to minimise IUC payouts to the older operators.Off-net traffic refers to voice call traffic going from one telco’s network to another’s. At present, Jio’s incoming to-outbound offnet traffic ratio is at 36: 64, according to data from the telecom regulator, which is why it is still a net IUC payer and not an earner, despite being voice minutes market leader with a 36% share, ahead of Airtel (33.5%) and Voda Idea (30.7%).For Airtel, it’s 54.7:45.3 and for Voda Idea, it’s 59.3:40.7.People close to Jio though dismissed the allegations, saying Jio’s network, on the contrary, is “being bombarded with missed calls from a vast swathes of ordinary 2G users of Voda Idea and Airtel who can’t afford the stiff voice tariffs on the minimum recharge plans. Jio circles reckon as much as 70% and 63% of Voda Idea and Airtel customers are still on 2G networks. “Jio continues to get missed calls from Voda Idea and Airtel 2G users due to the incumbents’ skewed voice tariffs.”On Thursday, Vodafone Idea and Airtel shares closed nearly 12% and 0.6% higher at Rs 5.44 and Rs 337.7 on BSE respectively. Shares of Reliance Industries , Jio's parent, closed 2.24% lower at Rs 1,178.70.“Were the IUC cut to be deferred, the biggest relief could be for Voda Idea which derived ~30% of its overall 1Q EBITDA from IUC. Bharti’s gains would be more muted, as IUC contributed as less than 10% of Ebitda,” Citibank said in a research note. “Jio would be negatively impacted, with IUC being a net cost to the company (about 18% of Jio’s 1Q EBITDA; Jio contributed around 22% of RIL’s consolidated Ebitda).”