@arunthl
Yes you are correct. Khata for all new layouts which fall out of BBMP circle will be given in BDA offices. If the layout is in BBMP limits and undertaken by BBMP from BDA, then khata has to be obtained from BBMP offices.

They have 4 bda offices in Bangalore (East, west, North, and South). Call sakala and approach the appropriate bda office. In Bda office they give you a list of documents. Some documents that I am aware of are:
1. Latest EC
2. Original Katha
3. Copy of Sale Deed
4. 3 Photographs
5. NOC from ...