Dear Akash/Madhav,
Supply of PKC and WAU are "service" as held by the Hon‟ble Supreme Court in Idea Mobile Communications Ltd. Vs. CCE &C, Cochin, C.A.No. 6319/2011 = 2011 (8) TMI 3 - SUPREME COURT OF INDIA and accordingly, liable to service tax. Similarly, domestic supply of CALs is incidental to the rendering of telecommunications service as held in the same case i.e. Idea Mobile Communications Ltd Vs CCE& C, Cochin. It would accordingly be liable service tax.
Also refer Ruling No. AAR/ ST/ 04/2013 In Application No. AAR/44/ST/09/2012 Applicant : M/s Microsoft Corporation (India) Private Ltd. = 2013 (9) TMI 110 - AUTHORITY FOR ADVANCE RULINGS, NEW DELHI
Regards,
Team YAGAY & SUN,
Management & Indirect Tax Consultants