These guidelines are applicable to all Domestic Scheduled Commercial Banks (excluding Regional Rural Banks, Payments Banks and Local Area Banks).
Scheduled Commercial Banks (other than RRBs, PBs and LABs) with past digital banking experience are permitted to open DBUs in Tier 1 to Tier 6 centres, unless otherwise specifically restricted, without having the need to take permission from Reserve Bank of India in each case.
Each DBU shall be housed distinctly, with the separate entry and exit provisions. They will be separate from an existing Banking Outlet with formats and designs most appropriate for digital banking users.
In addition to ensuring physical security of the infrastructure of the DBU, adequate safeguards for cyber security of the DBUs will have to be ensured by the banks
For further: https://www.rbi.org.in/Scripts/NotificationUser.aspx?Id=12285&Mode=0