Fantastic Real World Advice for Implementing NDI Workflows

In a recent article written by Eric Wenocur for Sound & Video Contractor, he discusses how using the right network switch is crucial to your NDI success. When you use NETGEAR M4250 or M4300 video over IP optimized switches your NDI workflow WORKS.

NDI can indeed be a powerful solution for simplifying video workflows in complex setups like the one you described. By leveraging the power of IP networks, NDI allows you to easily route video signals over Ethernet, eliminating the need for extensive point-to-point cabling.

With NDI, you can take advantage of the flexibility and scalability of IP networks to route video signals from multiple cameras, displays, and computers in your event space to the control room for production and distribution. NDI-HDMI and NDI-SDI converters can be used to interface with different types of video sources and displays, making it easy to integrate various devices into your NDI network.

One of the key benefits of NDI is its low-latency, high-quality video compression, which allows for real-time video transmission with minimal delay and high image quality. This is crucial for live events where timing and video quality are critical.

Additionally, NDI offers features such as multicast support, which enables efficient distribution of video signals to multiple destinations, and NDI PTZ (Pan-Tilt-Zoom) control, which allows for remote control of PTZ cameras over the network. These features can greatly enhance the flexibility and capabilities of your production setup.

Installing the software tools on his workplace computers allowed Eric to test out NDI—NewTek's software platform for video over IP—before he had any previous familiarity with it. Actually quite cool. He says it wasn't too difficult to send a live video stream, along with some color bars, between the two computers. It was impressive how the NDI apps identified each other and transported signals around on his home network. also quite basic, though.

Soon after, he became involved in a challenging hybrid event project where NDI appeared to be a good solution for eliminating most point-to-point SDI wire while allowing for the efficient movement of numerous signals. By transmitting signals over the Ethernet network wherever they were needed, NDI could basically replace an SDI matrix router. Ad-hoc configurations and flexibility are two areas where video-over-IP can excel.

At least four cameras and four displays are present in the event venue in this instance. These are linked to a control room with computers for a software production switcher (live feed), numerous Zoom participants, video playback, on-stage videowall, and tech control. additional screens are also included. Standard NDI compression, at around 130Mb/sec for 1080p60, is employed because this is a high-quality production environment. Both rooms of the system have several NDI-HDMI and NDI-SDI converters.

Production Network

Although it is a part of the organization's broader network's VLAN, the "production network" for this system has its own switches for all A/V and control traffic. Switches are the brains of a network and must be taken into account when implementing NDI on a big scale. Here, there are two sizable NETGEAR M4300-series switches—one in the control room and one in the event space. There is a substantial pipe between the rooms because to the switches' numerous 1Gb ports and their connections to one another via 10Gb ports. Although the switches also offer fiber SFPs, CAT6A cable works quite well at the required distance. 

Reduced stream duplication and mDNS for device identification are essentially only possible with managed switches that have strong multicast capability. Another reason for the need for robust switches is that the switch's backplane bandwidth must be adequate to handle all of the anticipated traffic on the 1G and 10G ports. On half of the ports of both switches, POE is also supported, which is beneficial (nearly necessary) for all of the deployed NDI cameras and converters. (Remember that while POE is very convenient, it has limitations on the overall power capacity of the switches and the ports.)

With NDI, it can be both a blessing and a burden for a receiving device to only "ask" for a stream from a transmitting device. Getting signals where you need them is simple, but every new connection could add another 130Mb stream to the network in some locations. There may be choke points in the network where having too many streams causes problems.

An example of this is a computer running software to create multiviews (such as Birddog’s NDI Multiview app). Both the multiview outputs to displays and any source that appears in a multiview grid are incoming streams to that computer. In contrast to the standard 800Mb recommended for a 1Gb interface, an 8-source window may use over 1000Mb of data flow on the computer's NIC and the switch port. Would it be sensible to use the more compact NDIHX for multiview? Maybe, but only if the hardware supporting it (and, in the case of cameras, being able to simultaneously create full and HX streams) is there. For the encoding and decoding involved in these configurations, connectivity of at least 1Gb is usually necessary, as well as a reasonably powerful computer. 

The main idea is that forming NDI connections randomly has consequences; if you watch the video, a stream is coming from someplace. The source may use less bandwidth while using multicast, but each recipient still receives a separate stream from the switch. Of course, manufacturers are promoting 4K NDI solutions, which are fantastic if you need them but demand a significant amount of bandwidth (250–400Mb/s per stream).

Also worth mentioning is that while NDI's "plug and play" design is convenient at first, managing a large number of endpoints can be time-consuming. It's not always obvious who is who, and sources and destinations don't always surface right away. Endpoints use their system names in NDI apps like Birddog's Central control app. The settings page for that device will open in a browser when you click one (let's say for a camera). However, you need to know the device's IP address if you wish to visit the configuration page without using an NDI app. Therefore, it is advised to assign static addresses and maintain an accurate list.

Read the full article from Sound & Video Contractor HERE