One example method of operation may include receiving a call message associated with a call, determining a service provider network identifier based on a telephone number of a call origination device, identifying, from the call message, an identity header with a link to a public certificate repository storing a public certificate assigned to a service provider network hosting the call origination device, retrieving a service provider code assigned to the service provider network from the public certificate, and determining whether the service provider code matches the service provider network identifier as identified from a verification table.