Setting the ball rolling for the implementation of the first phase of conditional access system, the government on Friday issued a notification that will bring parts of Delhi, Mumbai and Kolkata and the whole of Chennai under the new regime from September 1.

Coming after a month of confusion and hard bargaining, the notification makes it mandatory for cable operators in the notified zones to transmit pay channels through an addressable system for which set top boxes will be necessary.

The government decided to defer the July 15 implementation after an agreement was reached last week at a meeting with all stakeholders -- broadcasters, cable operators and multi-system operators.

Superseding its earlier order dated January 14, the information and broadcasting ministry's notification on Friday sets March 1 as the date within six months of which the law will come into force.

Besides the Chennai Metropolitan area, among the places that have been notified are Nariman Point, Cuffe Prade, Fort, Marine Drive, Church Gate, Dadar and Mahim in South Mumbai.

Most areas of south Delhi and some parts of central Delhi including Vasant Vihar, Safderjung, Maharani Bagh, SP Marg, Wellington Crescent and Parliament House will go under the CAS regime in the first phase of the staggered roll-out.

Most of Kolkata, including areas around Tolly Nalla and Behala, besides large parts of 24 Parganas will come under CAS from September 1.

The government estimates that nearly 300,000 set-top boxes would be in the country by the end of July, enough to cover the demand in the notified areas.

While south Delhi has 240,000 cable homes and an estimated requirement of 40,000-45,000 set-top boxes, south Mumbai has 410,000 cable subscribers and the requirement of set-top boxes could be as high as 80-90 per cent.

As far as Kolkata and Chennai are concerned, the government after an assessment of the two cities, does not anticipate a high demand for set-top boxes as the consumers there are not very interested in the Hindi pay channels.

According to the agreement reached last week at the Prime Minister's Office, all cable TV consumers in the four metros will pay only Rs 72 plus taxes for all channels from August 1 till the time they get notified for CAS.