History of telephony in India
1986-87	The first digital exchanges bring world class technology to India.
1987-88	Large-scale introduction of push buttons telephones that made dialing easier.
1988-98	Telecom bureaus provide various services – local, STD/ISD payphones, telex, fax and so on, all under one roof.
1991-92.	Introduction of I-net services.
1991-93.	Voice Mail Services are introduced
1991-96.	More new services, such as automatic changed number announcement on interactive voice response system, computerised fault repair, multimedia center with video conferencing, cellular phones and internet introduced
1991-97	ISDN services start.
1991-98	Introduction of services such as wireless in Local Loop, single window customer services management system, voluntary deposit scheme, toll free, helpline and computerised billing complaint.