For many reasons Ethernet-based Video-over-IP systems are becoming increasingly popular in both commercial and residential environments. They have flexible and highly-scalable system architecture which means inputs and outputs can be combined in almost any combination to suit the application. They also use low-cost Ethernet switches, replacing expensive, proprietary matrix switches.
Some other benefits include:
- low-cost and simple wiring - standard Cat5e/Cat6 cabling is used.
- flexibility with video connectivity - manufacturers such as Gefen produce systems that allow any-to-any transmission between connection-types (HDMI <-> DisplayPort, DisplayPort <-> DVI, DVI <-> VGA, VGA <-> HDMI, etc.).
- advanced functionality - video walls and multi-views can be easily configured using low-cost end points.
These advanced functionalities require enterprise-grade, full-featured Ethernet switches to deliver glitch-free, reliable video. While many low-priced residential-grade switches boast '1Gps ports', they lack backplane bandwidth, CPU power, stability and the advanced functionality required to make the Video-over-IP application function correctly. It is vital to understand that the quality of the Ethernet switch determines the reliability, performance and quality of the Video-over-IP application.
Important switch characteristics for a great Video-over-IP experience include:
- Port speed must be sufficient for the video protocols in use: 1Gbps is widely used to deliver great-quality compressed video; 10Gbps is used by some Video-over-IP manufacturers to deliver uncompressed 4k video at some frame rates and colour depths.
- Full-duplex ports: all ports must be able to offer the full speed (1Gbps or 10Gbps) upstream and downstream at the same time.
- Backplane capacity must be sufficient to be fully non-blocking, including capacity for the uplinks (ports connecting between switches).
- example: a switch with 48 x 1Gbps ports and 4 x 10Gbps uplinks requires backplane bandwidth of (48 x 2 x 1) + (4 x 2 x 10) = 176Gbps.
- Multicast support is essential to allow one input stream to be received by multiple receivers (a bit like putting multiple addresses in the 'to' field of an email, rather than sending individual emails to multiple addressees).
- VLAN (Virtual LAN) capability can be used to partition switches, completely segregating Video-over-IP traffic from general office or other systems traffic.
- IGMP snooping/query is used by the switch to direct multicast traffic only to the ports that want to receive it.
- Fast Leave (also known as Immediate Leave and Prompt Leave) is used to quickly disconnect a multicast stream from a port that no longer requires it; this avoids glitches and delays when a receiver changes from one video source to another.
- Quality of Service (QoS) allows the switch to prioritise identified video traffic.
- Static Routing is required by some Video-over-IP control systems.
- If the Video-over-IP senders (encoders) and receivers (decoders) use PoE (Power over Ethernet = power delivered from the switch through the Cat5e/Cat6 cable, avoiding the need for separate power packs for the senders and receivers), then the switch must have a very stable PoE power supply, with sufficient capacity to meet the needs of the powered devices.
The Niveo | Professional family of enterprise-grade Ethernet switches (distributed in Australia by Amber Technology) represents a great option for AV systems installers, for the following reasons:
- designed by AV professionals for AV professionals
- equipped with all of the required technical characteristics set out above
- tested and supported for virtually all mainstream Video-over-IP systems available today
- best PoE+ power supplies in the industry, with self-healing PoE technology (detects a ‘frozen’ device after a defined number of failed ‘pings’, and then automatically cycles the PoE power to restart the device)
- every switch burn-in tested for 72 hours before shipping from factory
- ten year warranty
- many models available with rear-facing Ethernet ports (makes AV racks look neat and tidy)
- never offered for sale on the Internet - never be 'shopped' against no-value-add box-movers compromising solution design or profitability.