摘要 |
A device including a receiver to receive a media stream including media content for a plurality of services, the content packed into packets each having a header and payload including a part of the content of one of the services, a mapping table(s) directly or indirectly mapping, the services to packet-IDs such that each service is mapped to one packet-ID, thereby enabling the packets including the content of a service to be identified via the packet-ID identifying that service, encrypted packet-IDs such that each packet includes its encrypted packet-ID in its header, and a packet filter to derive the packet-ID of that service from the mapping table(s), calculate the encrypted packet-ID from the derived packet-ID, and filter, from the media stream, the packets with the header including the calculated encrypted packet-ID yielding the packets including the part of the content of that service. Related apparatus and methods are also described. |