February 2020


The I&B Ministry's Top Bureaucrat Has Been Replaced

TV broadcasting services through Digital Addressable Systems (DAS) have been implemented vide 3 key regulations issued by TRAI in 2017, viz:

  1. Interconnection Regulations,
  2. Quality of Service Regulations and
  3. Tariff Order

The Interconnection Regulations specify the technical & commercial arrangements between Broadcasters & Distributors (DPOs) as well as between Distributors (DPOs) & Local Cable Operators (LCOs) for providing television services to the consumers.


The Interconnection Regulations require the DPO (Digital Platform Operator - CATV or DTH) to audit their entire system consisting of the equipment and software. The DPO is required to get the audit done atleast once a year.

Audit is an official inpection of the system, by a qualified outside party. TRAI has already identified 14 DAS auditors. Their contact details are listed in Table 1.

Pay Broadcasters Can Demand An Audit Approval Before Providing Pay Channels

The audit has 2 primary aims:

  1. To ensure that consumers receive Good Quality signals at their TV sets.
  2. Broadcasters are assured that the systems accurately record and bill Pay channels to consumers and the correct statements and revenues are passed on to the broadcasters.

Hence broadcasters can demand an audit approval of the DPO, even before they provide their pay channel feeds to the DPO. TRAI refers to this as a 'Broadcaster Caused Audit.'


On 8 November 2019, TRAI released its 94 page Digital Addressable Systems Audit Manual, that details a welldefined audit procedure. The manual was drafted by a committee consisting representatives from:

  • Broadcast Engineering Consultants India Limited (BECIL)
  • Indian Broadcasting Foundation (IBF)
  • News Broadcasting Association (NBA)
  • All India Digital Cable Federation (AIDCF)
  • Tata Sky
  • Dish TV India
  • Bharti Telemedia.
  • Sun Direct TV

After its consultation 'The Telecommunication (Broadcasting and Cable) Services Digital Addressable Systems Audit Manual on 29 March 2019, and subsequent open house discussions, TRAI released the audit manual, which may be reviewed periodically, owing to technical or techno-commercial changes, market developments and changes in the systems.

The Audit Manual is proposed as a guidance document. It does not supersede any provision(s) of the regulations. In case of any discrepancy between the Interconnection or other regulations, the regulations/ tariff Orders will prevail.


Audit has been broadly classified as either:

  • Pre-Signal or Compliance Audit &
  • Subscription Audit.


The audit will be called 'Pre-Signal Audit' if it is carried out before receiving Pay Channel feeds by the DPO, otherwise it willl be called a 'Compliance Audit.' According to regulations, before requesting Pay Channels, DPOs must ensure that their addressable systems meet the requirements as specified in the Schedule III of the Interconnection Regulations 2017. It is not compulsory for the DPO to get a pre-signal Audit conducted, but must provide a written declaration to broadcasters regarding Schedule III compliance along with:

  • CAS certificate provided by vendor.
  • SMS certificate provided by vendor.
  • STB certificate provided by vendor.
  • BIS compliance certificate.


Sub-regulation (7) of Regulation 10 of the Interconnection Regulations 2017 specifies that if a broadcaster, suspects the DPO's addressable system does not meet the specified requirements, & has not been audited during the past 12 months, the broadcaster can demand a Pre Signal Audit of the DPO, which will comprise of only a technical audit.

Every DPO Must Conduct A SMS & CAS Audit Once Per Calander Year, Within 18 Months Of The Previous Audit


Every DPO is required to conduct an audit, once in a calander year, of its Subscriber Management System, Conditional Access System and other related systems by an auditor to verify that the monthly subscription reports made available by the distributor to the broadcasters are complete, true and correct.

If if any changes are made to the SMS or CAS configuration or version, the DPO must notify the broadbasters within 7 days.

There should not be a gap of more than 18 months between audits of 2 consecutive calendar years.


  • Walk-through of the main head-end/s where CAS and SMS servers are deployed.
  • Validate the Headend diagram for equipment installed.
  • Check IP configuration to confirm & identify live & proxy servers. This shall include IP credentials of all the servers including the MUX.
  • Take inventory of IRDs + VCs issued by broadcaster including their serial numbers. Note boadcasters IRDs + VCs at site, but not installed.
  • Check MUX configuration to validate number of Transport Streams ("TS") configured with SID, scrambling status of each SID and ECM and EMM configuration (MUX-TS Stream-No. of ECM & EMM configured)
  • Take screenshots of all TS streams from MUX and compare with results of field TS recorded randomly at minimum 2 locations by auditor.
  • Take information of QAMs installed & powered to identify streams available for local insertion by LCOs.
  • Obtain record of PSI/SI server to confirm EPG, LCN etc. details.
  • Check PSI/SI server that it has EPG push capability.
  • Confirm insertion of watermarking network logo for all channels from encoder end. Only the encoders deployed after coming into effect of the Amendment Regulations shall support watermarking network logo for all pay channels at the encoder end.
  • Use FTA cable box/ TS analyzer to confirm that all channels are encrypted.
  • Walkthrough and understand the customer acquisition process and verification of sample CAF and PAF forms available with DPO.
  • Verify that Data Extraction (method & procedure) from CAS and SMS is as specified in the section 7 and section 16 of the Audit Manual.


  • Valid DAS license from MIB.
  • BIS certificates for all STBs deployed.
  • Certificate from all the CAS vendors
  • Certificate from SMS vendors
  • Block Schematic of Head-end including CAS & SMS.
  • Signed and stamped compliance audit.
  • Certificate from STB vendor.
  • List of all the decoders with VC serial numbers issued by broadcasters to DPO.

Auditors Must Inform TRAI Of Any Non Compliance Found During Audit


The audit must be conducted only by TRAI approved auditors.

DPO must inform broadcasters of the audit schedule, atleast 30 days in advance. Broadcasters must then provide TS recordings and VCs (if any) for verification during audit.

DPO must be informed of the documents it has to submit.

On completion of DPO caused audit, DPO receives the report which must be shared with broadcasters, when requested.

For broadcaster caused audits, both - DPO & broadcasters receive the report.

If the audit report is non-compliant, the auditor must inform TRAI.


Section 7A provides detailed step-by-step procedures for inspection of CAS & SMS compliance.

Section 7B provides detailed step-by-step procedures for verifying visible and covert (hidden) fingerprinting.

Section 7C states detailed procedures for auditing STBs, including their full compatibility with the deployed CAS, SMS & BIS certification.

Pre-Signal / Compliance Audit Ideally Completed Within 3 Weeks


Every Pre-Signal / Compliance audit should be ideally completed within 3 weeks and the proposed suggested timelines under compliance audit are mentioned below.

Audit visit at DPO: 1 week excluding travel time.

1 to 2 weeks maximum for the analysis of the data and finalization of the audit report.

One week time given to DPO to respond to issues flagged by auditor.

In case whether verification and analysis of TS recording and ground VC are also required the auditor may take an additional 1 week.

A Subscription Audit Verifies That Monthly Subscription Reports To Broadcasters Are Complete & Correct.


Regulation 15 of the Interconnection Regulations 2017 specifies that every DPO must carry out an audit once a calander year, of its Subscriber Management System, Conditional Access System and other related systems by a TRAI approved auditor.

The aim is to verify that the monthly subscription reports given to broadcasters are complete, true & correct. An error of upto 0.5% of the billed amount is permitted.

This audit is called 'Subscription Audit,' and the audit fee is borne by the DPO.

If a broadcaster is not satisfied, it can initiate a subscriber audit of the DPO, at its own cost, not more than once a calander year. If the audited error exceeds 2%, the DPO must bear the cost of the audit.

If the audit reveals additional amount is payable to the broadcaster, the DPO must pay such amount, along with the interest at the rate specified by the broadcaster in the interconnection agreement, within 10 days.


The scope of the subscription audit is limited to validation of the monthly subscriber report submitted by DPO to every broadcaster. However, to ensure sanctity of data, checks regarding integration of CAS and SMS will also be carried out by the auditor before data extraction.

The auditor will verify the integration of the CAS and SMS by performing few simulation tests on sample STBs such as activation/deactivation, fingerprinting and messaging command and generating respective reports from both SMS and CAS. The auditors will then check the SMS and CAS logs also regarding command execution timings to validate the integration between CAS and SMS.The TRAI audit manual provides detailed procedures and tests for this audit.

The auditor will ensure that no parallel SMS or CAS systems which are not reported by DPO are deployed in the headend.

The auditor must reconcile LCN & Genres declared by broadcasters with the actual LCN and genre at the headend.

The First Subscription Audit Will Not Be Later Than 1st April 2019


  • Valid DAS license issued by MIB
  • Certificate from all the CAS vendors (as per format).
  • Certificate from SMS vendors (as per format)


Every DPO must generate a state wise active/deactive STB count for the audit period.


It is detailed in the audit manual, and is broadly similar to the methodology applicable for pre-signal or compliance audits.


All DPOs must conduct a subscription audit within a calendar year, with a gap of atleast 6 months & not more than 18 months between audits. Further, the first subscription audit will not be later than 1st April 2019.


Auditors must complete the subscription audit & submit their reports after visit, within:

4 weeks for subscribers above 5 lakhs.

3 weeks for subscribers below 5 lakhs.

If verification & analysis of TS recording and ground VC are also required, the auditor may take additional 1 week.



Some of the important responsibilities for Distribution Platform Operator (DPO) include:

  • Abide by the Interconnection Regulation 2017 related to Audit.
  • Ensure compliance of the CAS, SMS and STB & undertake the compliance & subscription audits every calendar year.
  • Retain CAS & SMS data for at least 2 years after audit.
  • For JVs with shared CAS and SMS, the complete data of all JVs must be submitted to the auditor. Hence, it's advisable for such DPOs to conduct audit of all JV companies simultaneously.
  • Inform the broadcasters of the audit schedule at least 30 days in advance.
  • Share relevant portions of report with concerned broadcaster.
  • Inform & reimburse Broadcasters if variance in numbers exceeds 0.5%.
  • Cooperate & assist the auditor.


  • Abide by the Interconnection Regulation 2017 related to Audit.
  • Ensure correct TS recordings & ground VC samples (if any) are provided to auditors.
  • Not Interfere but support auditor with info on fingerprint schedule, help in physical verification of sample TS
  • If audit is caused by the broadcaster, not more than 2 broadcasters' representatives to observe the audit proceedings.


  • Abide by the Interconnection Regulation 2017 related to Audit & terms and conditions of the empanelment by TRAI.
  • Carry out audits in an objective, transparent and impartial manner.
  • Maintain confidential, all data extracted & information collected during audit.
  • Verify with DPO's systems, TS recordings provided by broadcasters.
  • Subscription audit period not to exceed 18 months for DPO caused audit & 24 months for broadcaster caused audit.
  • No data dump to be carried outside DPO's premises, for analysis.
  • Not argue or cause dispute with the DPO during audit. Any non-cooperation by DPO, should be conveyed in writing.
  • DPO's views / justifications must be mentioned in the audit report.
  • Inform TRAI of any non-compliance by DPO.
  • The Auditor shall not undertake audit of addressable system of any service provider for whom the Auditor is also the statutory auditor or internal auditor or concurrent auditor or where the Auditor is the consultant to the service provider.
  • The Auditor shall not undertake audit for more than 3 consecutive years.
  • Any discrepancy observed must be conveyed to TRAI.
  • TRAI may remove any Auditor for 2 or more wrong audits.


TRAI's Digital Addressable Systems Audit Manual is a very detailed and exhaustive text of more than 90 pages. it is available for free download from : (

This article only highlights certain key topics and requirements, and hopes to provide an overview of the different type of audits & their DAS audit procedures. For specific, detailed information, TRAI's audit manual must be referred to. n