Hence, all legal ("white") telecom traffic to the country is subject to the rates imposed by these corporations.
To overcome this restriction for the purpose of achieving lower costs for consumers, and to make a profit in the process, many small parties set up VoIP routers in homes and offices around India.
Telecom traffic from other countries is sent to these VoIP routers via IP and terminated to the local Indian PSTN.
These are normally operated clandestinely in third-world calling destinations as the "black" end of a "grey route" where conventional private branch exchange lines (such as T-carrier primary rate interface) are not available to VoIP operators due to a hostile local regulatory environment.
[1] By using licensing restrictions and regulations to ensure that the interconnection between the PSTN/PLMN network and Internet is not permitted, the government in India delivers a lucrative monopoly to International Long Distance (ILD) service providers licensed under Section 4 of the Indian Telegraph Act as the only carriers officially allowed to carry international long distance traffic into India.