RIST solves a problem by transforming unmanaged networks into reliable paths for video contribution. This comes amidst increasing interest in using the public internet to contribute video and audio. This is partly because it is cheaper than dedicated data circuits, partly that the internet is increasingly accessible from many locations making it convenient, but also when feeding cloud-based streaming platforms, the internet is, by definition, part of the signal path.
Packet loss and packet delay are common on the internet and there are only two ways to compensate for them: One is to use Forward Error Correction (FEC) which will permanently increase your bandwidth by up to 25% so that your receiver can calculate which packets were missing and re-insert them. Or your receiver can ask for the packets to be sent again.
RIST joins a number of other protocols to use the re-request method of adding resilience to streams which has the benefit of only increasing the bandwidth needed when re-requests are needed.
In this talk, Ciro Noronha from Cobalt Digital, explains that RIST is an attempt to create an interoperable protocol for reliable live streaming – which works with any RTP stream. Protocols like SRT and Zixi are, to one extent or another, proprietary – although it should be noted that SRT is an open source protocol and hence should have a base-level of interoperability. RIST takes interoperability one stage further and is seeking to create a specification, the first of which is TR-06-1 also known as ‘Simple Profile’.
We then see the basics of how the protocol works and how it uses RTCP for singling. Further more RIST’s support for bonding is explored and the impact of packet reordering on stream performance.
The talk finishes with a look to what’s to come, in particular encryption, which is an important area that SRT currently offers over and above reliable transport. Watch now!
With all the talk of the SMPTE ST 2110 standards suite, it’s sometimes forgotten that it only deals with content. If you want a working system, you’ll need to do a few more things – find new devices on the network, work out what they can do, control them, guarantee the bandwidth and often deal with metadata that arrives separately like tallies.
This is what the AMWA NMOS specifications do. Peter Brightwell and Thomas Edwards have been heavily involved in creating them and in this video lead us through what each one does and how they are used.
AMWA’s discovery and registration protocols IS-04 and IS-05 play a big role in making IP systems usable, allowing the system to easily identify new kit when it’s plugged in and understand its capabilities. However, deploying such systems at scale should give anyone pause for thought – how scalable are they? How does the system recover after a network outage? Clearly we wouldn’t want the system to be brought down by the administrative burden.
Rob Porter, from Sony Europe Ltd., has done the research and presents it here at the VSF’s IP Showcase at the 2018 IBC.
Rob gives a brief overview of the two specifications, describing their APIs and the open source nature of them. He then goes on to explain how he emulated this large number of devices and what he found.
Finally, Rob wraps up the session by explaining how he optimised network-loss recovery times and summarises best practices.
An increasing amount of broadcast video is travelling over the public internet which is currently enabled by SRT, Zixi and other protocols. Here, Merrick Ackermans explains the new RIST specification which aims to allow interoperable internet-based video contribution.
Speaking at the IP Showcase at IBC 2018, Merrick covers:
John Mailhot from Imagine Communications discusses what ‘Full Stack’ means for video over IP. The SMPTE 2110 suite of standards is mainly about the transport of essences – but how to you simply plug in some equipment and get going? You need standards which discover and register the new device, you need timing to synchronise devices. It’s a whole ecosystem.
John walks us through the data flows (and workflows) necessary when you plug new 2110 kit in and we quickly discover there is more depth than we imagined.
John also discusses how DHCP can give you more than just IP addresses.
Covering IS-04, IS-05, PTP/SMPTE 2059, ST 2110 and IEE 802.1AB (LLDP). This is a very practical video. Why? Because understanding all this is key to diagnosis and troubleshooting.