Patent ID: 8774168

Claim:
A method comprising: from each of one or more first user terminals of a respective one or more users, receiving a respective first indication via a first communication network via a first interface between each respective first user terminal and a communication service; conditionally verifying each of said users of the first user terminals as being authorized to participate in a conference associated with the communication service based on the first indication received via the first interface; from one or more second user terminals of a respective one or more users, receiving a respective second indication via a second, alternative interface over a second communication network between each respective second user terminal and the communication service, wherein the second interface is not operable to provide the first indication; verifying whether a same Personal Identification Numbers (PIN) has been received from at least two separate users; responsive to verifying the same PIN has been received from the at least two separate users, removing the at least two separate users from the conference associated with the communication service; conditionally verifying each of said users of the second user terminals as being authorized to participate in the conference associated with the communication service based on a second indication received via the second interface; and verifying at least one of said users of the first user terminals or at least one of said users of the second user terminals has a license associated with using the communication service to multicast participant audio to all users authorized to participate in the conference over at least the first and second communication networks, the verifying the at least one of said users of the second terminals comprising mapping the second identifier received over the second communications network to a first identifier associated with the at least one of said users of the second user terminals, wherein responsive to determining that at least one second indication comprises a second user identifier associated with the respective user of the second user terminal, the method further comprises: enabling storing a first user identifier for each of the users of the first and second user terminals, wherein the second user identifier associated with the respective user of the second user terminal is an identifier other than the first user identifier associated with said respective user of the second terminal; and enabling an additional check of each respective user of the second user terminals associated with each respective second user identifier based, at least in part, on a respective mapping between the second user identifier and respective first user identifier.