Network Service Provider:
A network service provider (NSP) is a business or organization that sells bandwidth or network access by providing direct backbone access to the Internet and usually access to its network access points (NAPs). For such a reason, network service providers are sometimes referred to as backbone providers or internet providers.
Network service providers may consist of telecommunications companies, data carriers, wireless communications providers, Internet service providers, and cable television operators offering high-speed Internet access. ( Source: Wikipedia)