Method for operating a broadband access network of a telecommunications network with a customer premises equipment, wherein the broadband access network comprises at least one access node (151, 152, 153), wherein a specific access node of the broadband access network is enabled to operatively connect the customer premises equipment to the telecommunications network in view of providing communication services and/or communication access services to a user related or connected to the customer premises equipment, wherein the broadband access network is able to provide communication access services to the customer premises equipment by means of providing a whole sale interface to a service provider, wherein the service provider is able to provide communication services to the customer premises equipment and/or to the related or connected user using the whole sale interface and the broadband access network, wherein, in case that the customer premises equipment is unknown to the telecommunications network or has previously not been connected to the telecommunications network, a whole sale entity is involved, wherein the whole sale entity is separated from both the broadband access network and the service provider, wherein, in view to realize or to prepare the operational usage of the customer premises equipment, the method is characterized by comprising the following steps: -- in a first step, the whole sale entity transmits an authentication request to the service provider using a first application programming interface, the first application programming interface being exposed by the service provider, -- in a second step and in case of the authentication request having been granted, the whole sale entity transmits a configuration command to the broadband access network using a second application programming interface, the second application programming interface being exposed by the broadband access network. wherein a specific access node of the broadband access network is enabled to operatively connect the customer premises equipment to the telecommunications network in view of providing communication services and/or communication access services to a user related or connected to the customer premises equipment, wherein the broadband access network is able to provide communication access services to the customer premises equipment by means of providing a whole sale interface to a service provider, wherein the service provider is able to provide communication services to the customer premises equipment and/or to the related or connected user using the whole sale interface and the broadband access network, wherein, in case that the customer premises equipment is unknown to the telecommunications network or has previously not been connected to the telecommunications network, a whole sale entity is involved, wherein the whole sale entity is separated from both the broadband access network and the service provider, wherein, in view to realize or to prepare the operational usage of the customer premises equipment, the method is characterized by comprising the following steps: -- in a first step, the whole sale entity transmits an authentication request to the service provider using a first application programming interface, the first application programming interface being exposed by the service provider, -- in a second step and in case of the authentication request having been granted, the whole sale entity transmits a configuration command to the broadband access network using a second application programming interface, the second application programming interface being exposed by the broadband access network. -- in a first step, the whole sale entity transmits an authentication request to the service provider using a first application programming interface, the first application programming interface being exposed by the service provider, -- in a second step and in case of the authentication request having been granted, the whole sale entity transmits a configuration command to the broadband access network using a second application programming interface, the second application programming interface being exposed by the broadband access network.