With Bsnl connection opt for a TYPE II Type B modem
Cost Rs 1600/+ taxes. Rental Rs 80/= P.M
ADSL modem+4portLAN + wifi ( 3-in-1)
[url=http://www.calcutta.bsnl.co.in/dataoneinstall/menu.html]BSNL BROADBAND MAIN MENU[/url]

Para two:
Mention details of present ISP/Modem/router used.
Number of systems to be used. desktops/laptops/wifi cellphone etc.
I think Linksys wrt54g is only a router/wifi . will check up and update later.
REF:
[url]http://www.indiabroadband.net/bsnl-broadband/21244-utstar-wa3002-g4-quick-reference.html[/url]