Section 2(1)(t) in Standards of Quality of Service of Basic Telephone Service (Wireline) and Cellular Mobile Telephone Service Regulations, 2009
(t)"Stand-alone Dedicated Control Channel" or "SDCCH" means, a GSM control channel for signaling purposes where the majority of call setup occurs, which is used for communication between mobile station (MS), i.e, mobile handset and Base Transceiver Station (BTS) before such mobile station is assigned a Traffic Channel (TCH);