Every government security in India exists as an electronic entry in the Subsidiary General Ledger maintained by the RBI. Every trade in that security settles through SGL transfer. Every auction is conducted on the e-Kuber platform. Every secondary market trade happens on NDS-OM. And every Primary Dealer has a daily obligation to make markets in these securities — quoting two-way prices so that any bank, insurance company, or mutual fund can buy or sell at any time.
This infrastructure — built over two decades through 611 NDS/SGL notifications, 807 Primary Dealer notifications, and 741 auction notifications — is what makes the G-Sec market liquid enough to serve as the transmission mechanism for monetary policy.
See also: Government Securities & Money Market
For the narrative version, see How India Built Its Bond Market