In telecommunication, a complementary network service (CNS) is a means for an enhanced-service provider customer to connect to a network and to the enhanced service provider.
Complementary network services usually consist of the customer local service, such as a business or residence, and several associated service features, such as a call-forwarding service.
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This article incorporates public domain material from Federal Standard 1037C. General Services Administration. Archived from the original on 2022-01-22.