A method of transmitting a transport stream over an IEEE 1394 Serial Bus comprising stripping out of the transport stream identifiable unrequired data so as to reduce the bandwidth of the transport stream, a digital multi-media receiver for transmitting a transport stream to a Conditional Access Module on an IEEE 1394 Serial Bus including a reader for reading the contents of the transport stream and identifying data which is not required for processing by a Conditional Access Module, a stripper for stripping out at least some of the identified unrequired data from the transport stream and a transmitter for transmitting all of the remaining data of the transport stream which has not been stripped and a network of digital multi-media devices connected by means of an IEEE 1394 Serial Bus whereby a first device sends such a stripped transport stream to a second device over the IEEE 1394 Serial Bus.