Ack packets on ethernet are minimally 64 bytes in size, 'loaded' downstream packets on typical PPPoA DSL deployments are usually 1492 bytes in size.
RFC1122 specifies "in a stream of full-sized segments there SHOULD be an ACK for at least every second segment".
Therefore your minimum ack bandwidth ratio is 64/(1492*2) = 2.15%, or 22,490 bytes of acknowledgements required per 1MB received, or as a bitrate approximately 110kbps (0.1Mbps) up per 5Mbps down.
For some reason I'm thinking they want your upstream bandwidth.
If their 'streams' were delivered as uniquely identified blocks of data, it would be trivial to have the devices cache all downloaded blocks and act as distributed storage. For live streams it is difficult because there is only one origin point for data blocks, but by giving each stream-viewing client a random 'block offset' starting point (equivalent to a broadcast delay of 0-30s) client demands can be spread across a range of blocks and clients can be leveraged to redistribute blocks to other clients. Block availability can be intelligently managed by the control server with new blocks being pushed initially to the clients with the highest upload bandwidth and those clients being instructed in turn to push data to another tier of clients.
If the devices have moderate local storage (64GB) then VoD / PVR services for recently-shown content would be trivial to implement at almost zero bandwidth cost to the provider. Individual devices would be instructed to retain or delete stream blocks as necessary to maintain sufficient block availability across the distributed storage network according to forecast/measured demand. Playback is achieved simply by requesting the relevant blocks and performing some local caching, with a central server available to guarantee availability if required.
1@rahuldottech So? TV can be transmitted over ADSL even if a cable connection is more usual. – DavidPostill – 2018-05-15T17:54:18.273
Do you need a smartcard with CI+ module? – Thomas – 2018-05-16T09:28:11.170