DisplayNet FAQ
What is DisplayNet?
DisplayNet is an award-winning system for AV distribution that leverages SDVoE technology to switch, extend and distribute uncompressed AV signals in real time over 10GbE Ethernet with resolutions up to 4K (UHD). DisplayNet provides unmatched image quality with zero frame latency and zero artifacts. DisplayNet also delivers unprecedented levels of scalability, versatility and reliability and supports a wide range of applications including Point-to-Point Extension, limitless Matrix Switching, Video Wall Display, and Multiviewer.
What signal types does DisplayNet support?
DisplayNet supports the following signal types: uncompressed HDMI / DVI (with or without HDCP), Embedded HDMI Digital Audio, Analog Stereo Audio, Downmixed Audio, Bidirectional IR, RS-232, USB 2.0 (if equipped), USB HID (if equipped), and 1GbE, all over a single 10GbE connection. These signal layers may be routed independently in different ways depending on the signal type.
What is the maximum resolution supported?
The DisplayNet Server supports uncompressed signals up to 4K /60p (4:4:4), at distances of up to 330 ft. (100 meters) over copper and up to 18 miles (30 kilometers) over fiber for each 10GbE connection using the recommended cables.
What types of compression does DisplayNet use?
For all resolutions up to 4K /30p, none. Rather than compressing video and audio signals, the SDVoE technology that DisplayNet is built around discards the TMDS synchronization layer at the source and reconstructs it in real-time at the destination. This is known as Adaptive Clock Resynchronization, or ACR. With ACR, 10.2Gb of HDMI-delivered data can be transmitted using only 6.7Gbps of bandwidth over Ethernet, allowing for sufficient overhead and the routing of additional streams over a single 10Gb Ethernet connection. Resolutions of up to 4K /30p (4:4:4) are supported with zero compression, zero frame latency, and zero image artifacts.
For 4K /60p signals, a light compression algorithm is used to compress the video signal, in addition to ACR. This is done to meet the bandwidth needs of 4K /60p signals, which can reach 18Gbps natively over HDMI. With both ACR and compression enabled, a 4K /60p signal uses approximately 9Gbps of bandwidth. The compression algorithm employed by DisplayNet is a proprietary codec, optimized for quality and low latency, with a compression ratio of only 1.4 to 1. Compressed signals are visually indistinguishable from the original source feed, and the maximum total latency in genlocked mode is 100 microseconds, well under a frame. With compression enabled, DisplayNet supports 4K /60p signals with zero frame latency and zero image artifacts.
How does DisplayNet transmit synchronous data using Ethernet?
DisplayNet uses specialized SDVoE technology, known as Adaptive Clock Resynchronization, or ACR to ensure synchronous delivery of AV signals over IP. Unlike other IP-based AV routing technologies, such as AVB and IEEE PTP, ACR allows for standard 10GbE network switches to be used, as all synchronization tasks are performed on the transmitter and receiver. Additionally, DisplayNet uses multicasting with IGMP snooping, allowing any number of receivers to subscribe to a single multicasted AV stream, rather than creating an individual stream for each receiver. Each transmitted signal layer is available for output at any combination of destination devices.
How much latency is present?
In Genlocked Mode, for all resolutions up to 4K /30p, the total latency is a maximum of 30 microseconds, which equates to several lines of video at the most and is undetectable to the human eye. For 4K /60p signals, the total latency is 100 microseconds, maintaining zero frame latency. In Genlocked Scaling mode, the total latency is 3 milliseconds, this is due to the use of the scaler in the unit and equates to less than 1 frame of video.
DisplayNet also includes Fast Switched Mode, which can enable seamless switching between sources with identical specifications. In this mode, the maximum latency is no less than 1 frame and no more than 2 frames of video. This translates to <6.7 milliseconds of latency at 30Hz, and <33.3 milliseconds of latency at 60Hz. This is in addition to any latency added by the display. For optimal low-latency performance, select displays with minimal input lag (less than 30 milliseconds is recommended).
How does DisplayNet genlock the displays without using an external sync?
Unlike the “House Sync” method, DisplayNet does not require an external signal.
DisplayNet employs SDVoE technology called Adaptive Clock Resynchronization, or ACR to guarantee synchronous data delivery and to genlock displays to sources.
When a receiver is set to Genlocked Mode, the HDMI input of the display connected to the RX is synchronized to the HDMI source.
Furthermore, when multiple RX devices are joined to a single TX, all displays are genlocked to the same source and therefore all displays are fully synchronized to each other.
Does DisplayNet support HDCP?
Yes, the HDMI connections on DN-300 and DN-200 transmitters and receivers are fully HDCP 2.2 compliant, while the 10GbE connection is compliant with the HDCP Interface Independent Adaptation Specification Rev 2.2.
All AV data transferred over 10GbE is encrypted using 128-Bit AES encryption.
What is the purpose of the 1GbE ports on the receivers and transmitters?
Each and every DisplayNet endpoint includes a fully functional 1GbE (10/100/1000 Base-T) Ethernet port, to be used by any standard Ethernet equipment at the endpoint. This allows for additional devices, such as control interfaces or access points, to be connected to the network over a single cable run. These ports also support third party Audio-over-IP solutions. Any connected device will reside on the same network used by DisplayNet.
What type of network switch does DisplayNet require?
DisplayNet is a platform based on SDVoE technology, meaning that almost any standard 10GbE network switch can be used. The 10GbE switch must support certain features. DisplayNet requires a non-blocking 10GbE Ethernet switch supporting Layer 2/Layer 3 communication, multicasting with IGMP snooping, as well as the Fast Leave option. Almost all currently available 10GbE network switches support these features.
How large of a network is possible?
Theoretically, DisplayNet is infinitely scalable and completely flexible with regard to input and output configurations. The system array is limited only by the number of installed endpoints and the number of non-blocking ports on the 10GbE network. Unlike a typical matrix switcher, individual ports are not restricted to only input or output. Some newer 10GbE modular switches can be stacked for greater expandability; however, any stacked configurations must be non-blocking (i.e., all ports must be able to access every other port without any limitations on bandwidth) for DisplayNet to function properly. For more information on the use of stacked switches for DisplayNet, please contact DVIGear technical support.
Is it possible to connect DisplayNet to an existing network?
Yes, but this is not generally recommended. One of the essential requirements for DisplayNet is that all connections to receivers and transmitters are non-blocking, as all 10Gb of bandwidth is needed for successful signal transmission. This is in contrast to more traditional uses of Ethernet networking, where blocking traffic may occur without impact to the end user. Unnecessary broadcast traffic, in particular, may cause issues with the operation of DisplayNet. Despite this, existing network switches may be used by placing DisplayNet devices on a separate VLAN. Please contact DVIGear technical support for further information.
What type of network cables does DisplayNet require?
For all 10GbE network connections, DVIGear strongly recommends the use of CAT-6A F/UTP (500 MHz) cables as this type of cable was specifically designed to support 10GbE traffic. While there are many manufactures of high-performance CAT-6A cabling, DVIGear recommends CAT-6A F/UTP cables with ZMAX terminations made by Siemon, which can be purchased by contacting Siemon. Cable terminations can be performed in a straight-through scheme using either the TIA/EIA T568A or T568B standards. However, T568B is the preferred termination scheme. Refer to the cable manufacturer for information on proper grounding techniques for network cables.
How far can the 10GbE connection be extended?
DN-300 and DN-220 transmitters and receivers support up to 18 miles (30 kilometers) of signal extension using resolutions up to 4K/60P (4:4:4) using the recommended Fiber Optic Media for the SFP+ module used. The extension distance between the TX and the network switch can be up to 18 miles. The connection from the network switch to the RX can also be up to 18 miles, for a total of up to 36 miles (60 kilometers) of signal extension. DN-210 transmitters and receivers support up to 300 ft. (100 meters) of signal extension using resolutions up to 4K /60p (4:4:4) with the recommended CAT-6A F/UTP type cables. The extension distance between the TX and the network switch can be up to 100 meters, and the connection from the network switch to the RX can also be up to 100 meters, for a total of up to 660 ft. (200 meters).
Can a DisplayNet transmitter and receiver be used in a point to point setup?
Yes, DN-300 and DN-220 transmitters and receivers allow for extension of up to 18 miles (30 kilometers) at resolutions of up to 4K /60p (4:4:4) using the recommended Fiber Optic Media. DN-210 transmitters and receivers can extend resolutions up to 4K /60p (4:4:4) over point-to-point extension distances of up to 330 ft. (100 meters) using the recommended CAT-6A cable. All signal layers (Analog Audio, Downmixed Audio, 1GbE, RS-232, and bidirectional IR) are automatically joined when the devices are in a point-to-point configuration.
How are DisplayNet endpoint devices controlled and managed?
DisplayNet systems must include a DisplayNet Server, which runs the DisplayNet API Engine required to control and manage the entire system. DisplayNet Manager software and other control devices do not communicate directly with the endpoints. Instead, they interface with the API Engine using the DisplayNet API, which includes all of the commands necessary to control small or large networks of DisplayNet devices.
Commands are sent from the control software and/or system to the API Engine over the standard Telnet protocol, and these commands are then translated by the API Engine and distributed to the DisplayNet devices via UDP over the 10GbE network. Commands are sent from the control software and/or system to the API Engine over the standard Telnet protocol, and these commands are then translated by the API Engine and distributed to the DisplayNet devices via UDP over the 10GbE network. The DisplayNet Server provides a central control interface between the control equipment/software and the DisplayNet endpoint devices; it is a required component in every DisplayNet system.
How do DisplayNet Manager and the DisplayNet API help streamline system design and setup?
DisplayNet Manager is designed to make the AV system integration and maintenance process easier from start to finish. The software can be used on a day-to-day basis for system control; but it primarily offers designers, programmers and other technical personnel the tools they need to efficiently assimilate DisplayNet into their existing workflows. It includes system setup and control features, as well as a console that displays how the DisplayNet API is used to perform control tasks sent using the software. Programmers can use these features to quickly set up a system and become familiar with the API commands used to perform system functions. The software can also save system configurations as snapshot presets, which can be copied and pasted into third party controller software. Additionally, the DisplayNet API enables all of the features of the software to be available for programmers at the API level. All of these rapid application deployment features offer system integrators the ability to streamline system design and setup.