QUIC only supports communication between two endpoints, such as between one server and one device. So it’s hardly the best choice, if you want to distribute video or data from one server to many devices simultaneously, which is exactly what broad- and multicast is all about.
But QUIC is built on the UDP protocol, which supports both one-to-one and one-to-many communication, allowing us to extend QUIC to support broadcast and multicast as well. In short, we made QUIC send data packets to clients without the clients sending anything back, think one-way street.
Then we can leverage UDP to distribute the QUIC data packets: one-to-all via broadcast networks (because we’ve IP-enabled broadcast) and one-to-many via IP multicast in broadband networks.
We could have used UDP, but there are lots of other benefits to using QUIC, such as retransmission of lost packets, which is normally handled by TCP – but not UDP. This is initiated by the client when it detects a packet is missing, so for broadcast we’re using a separate data connection over the normal internet for retransmission.
“With IP-enabled broadcast networks, we can send QUIC data packets anywhere we want – broadcast, broadband, you name it.”
However, retransmission tends to delay things (which is a problem for Low Latency streaming), and separate data connections aren’t always an option. Fortunately, we can easily add Forward Error Correction (FEC) to QUIC, greatly reducing packet loss.
Traditional broadcast also uses FEC, but because we use our LEAF™ to receive broadcast/multicast and retransmit as unicast, we can leverage new and advanced FEC technologies on any IP-enabled network, then transcast and retransmit to the user’s devices on the local network without any compatibility problems.
With IP-enabled broadcast networks, we can send QUIC data packets anywhere we want – broadcast, broadband, you name it. That just makes it insanely flexible, and with that kind of flexibility, we can use IP networks far more effectively and efficiently.
Networks and services deal with scale more effectively, because we can dynamically switch to the best network for the job. That directly translates into increased capacity, better reach, lower CAPEX and increased growth and ROI.
This isn’t just theory or a good idea – we are launching QUIC with FEC over ATSC 3.0 in the Copenhagen Testbed. Currently, we are planning PoC solutions with partners and customers in the USA (datacasting over ATSC 3.0 and 5G) and Africa (datacasting over DVB-T2).
If you want to dive deeper into the technical details, check out our IEEE article in SMPTE Motion Imaging Journal: https://lnkd.in/g_Fu4Yjj