Interconnect Usage Charge (IUC) is an obsolete concept that is associated with 2G networks, Reliance Jio's President (Network) Mathew Oommen said. He added that telecom operators must invest more in 4G before venturing into 5G or the industry would become obsolete. Jio recently said it has paid nearly ₹13,500 crore as net IUC charges to the other operators.