"The industry has developed various modules over the DLT framework, which have been reasonably successful, considering the noticeable decline in the volume of unsolicited commercial communications (UCC) originating from SMS over the last couple of years. But UCC from voice calls is still an issue that the regulator and operators are working together to address," S P Kochhar, director general, Cellular Operators Association of India (COAI), said Tuesday.
