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IP Routing -10 Facts You Need To Know
At $12Bn a year the IP switch market is approximately 40 times bigger than the SDI router market. This scale drives an investment in R&D - with consequent rapid development and reduced costs - that is simply impossible in the broadcast business. Broadcasters can benefit from this economy of scale and high velocity development but only if they stay with mainstream equipment. Building specialist IP switches for broadcast is a bad idea - it cuts us off from the IT future.
2. IP switches don't care about video format or compression
The format agnostic nature of IP switches provides real infrastructure flexibility. They can handle SD to 4K and beyond - any future format can be routed without needing to change the infrastructure. Similarly the switch neither knows nor cares if the media is compressed or not. The same infrastructure can handle full quality baseband or 100Mb AVCI or any compression scheme or schemes you choose to employ. Subject to the necessary bandwidth being available an IP infrastructure will handle anything you can throw at it - now and in the future.
3. Switch costs scale with bandwidth not ports
The cost of traditional SDI routers increases with the number of ports; IP routers increase in price as their total switchable bandwidth increases. So with (2) in mind this allows us to potentially save money by using compression - providing more switchable routes for a given cost. In the rest of the broadcast chain the use of compression is well accepted and proven to reduce costs but it's a new opportunity not available with SDI infrastructure. Definitely worth thinking about but like most things it has drawbacks as well as advantages.
4. Using compression saves on the switch but increases edge costs
The IP switch is format agnostic so using compression to reduce the aggregate bandwidth of the data to be switched is going to save money. However encoders and decoders are going to be required and these cost money. The more sophisticated the compression scheme the higher the compression ratio and therefore savings on the switch - but the more sophisticated the compression scheme the higher the codec costs. These codecs will be in edge devices as the IP switch is an off the shelf product (1). Analysis shows that using sophisticated codecs such as AVCI or JPEG2K total system costs could be 70% higher than using non-compressed throughout. However it is worth pointing out that even using AVCI still reduces costs by about 7% compared to SDI routing. Simple compression schemes could lower total system costs by 50% compared to non-compressed.
5. Proprietary compression schemes increase costs and limit flexibility
Compression can lower costs but using compression adds complexity. If more than one compression scheme is in use then the system needs intelligence to ensure signals are only routed to compatible destinations. Proprietary schemes may only be available using certain technologies or platforms which really limits flexibility - how can you spin up a software transcoder on demand in a data center if the compression scheme is only available in an ASIC? IP routing gives us the ultimate in flexibility - don't compromise that flexibility for a quick win with proprietary compression. Demand open compression schemes if you are going to use compression.
6. Layer 3 switching is better than layer 2
The layer refers to the seven layer Open Systems Interconnection (OSI) model - it's abstract but it matters. The higher up the layers you go the more sophisticated things become. In particular layer 3 enables distributed switching - multiple IP switches working together as a single routing infrastructure. You just can't do this with layer 2 without inventing proprietary solutions which lock you out from the IT mainstream. There are layer 2 solutions out there - be careful!
7. Clean switching is not an issue
Clean switching is possible with a format-agnostic off the shelf IP switch - it becomes a function of an edge device rather than the switch itself. Snell has demonstrated clean switching using a standard Cisco Nexus 3524 Switch. It works using 'make before break' - the edge device joins the new stream for as long as required to make the clean switch before dropping the old stream. This approach requires the edge device to be able to handle two streams momentarily but enables a standard IP switch to be used. Many routing operations do not even require clean switching but it was an integral part of SDI routers; providing clean switching only where it is required can reduce costs still further.
8. Common SDI and IP control systems simplify operation
It's likely that many facilities will transition to IP routing and will have SDI and IP routing in use simultaneously for some time. The practicalities and economics of real world production mean this transition may take many years. During that time a routing control system that works with both SDI and IP routing becomes an absolute necessity. Done well the control system can hide the routing technology from the user, allowing users to focus on the task rather than the technology. The control system can also provide this abstracted view to third party applications greatly simplifying system integration.
9. IP Routing brings new opportunities for automation and efficiency
IP Routing is more than a lower cost more flexible version of SDI routing. IP routing brings with it a completely new set of opportunities to make production and playout more efficient. Systems can auto-discover the capabilities of sources and destinations across locations and automatically switch in processing as required. As an example, consider how we handle a 1080p ASI stream that is needed in 1080i SDI in master control today. Intelligence is required to patch in the ASI decoder and the P to I converter and to set the various routes required. In the IP and Data center world everything can be handled automatically - even creating a new instance of the software P to I converter as required.
10. Quantel and Snell IP products available in 2015
Quantel and Snell IP products that make all these facts a practical reality will be launched in 2015. Planned products include IP stream i/o capability on Kahuna switchers and Sirius routers, the xStream platform and revolutionQ, plus IQ Modular edge devices that provide clean switching,. There will also be a new hybrid SDI/IP router control system to tie it all together. Talk to us now about introducing IP routing into your facility.
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Related Keywords:IP Routing, IP Switchers, 4K Video, Encoding
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