January 23, 2013, 10:13 by Chris Perry

In the course of my sales engineering work at TelVue, a lot of clients have expressed confusion over the nature and the value of IP (Internet Protocol) broadcast.  This blogpost is an attempt to clear the air.  Comments are welcomed, below.

Firstly, we are often asked why a broadcaster should migrate to IPTV — to which I usually respond that IPTV is inevitable, and a station has three choices in the current broadcast environment:

  1. Stay on your existing system until it dies
  2. Jump on to an SDI or other intermediate platform that tends to be expensive and will have a finite life
  3. Or make the jump to IPTV now, and be closer to the cutting edge.  Adapt by choice, before you find you have no other choice.   You can even make the transition in phases.  For example,  I have designed ways to put IPTV into half of a system, while leaving some of the old analog stuff in place.  (That’s what TelVue’s ProVue Decoder and 3rd party encoders are all about).

Secondly, there seems to be a common misperception that an IP broadcast server like the TelVue HyperCaster is an Internet-based product.  It is NOT, and here is why: the HyperCaster sends a high-quality IPTV signal over the Local Area Network (LAN), not to the public Internet.  To delve a little deeper, the HyperCaster sends out a UDP stream.  UDP (User Datagram Protocol), like the TCP protocol that Web users are more familiar with, is part of the Internet protocol suite.  UDP is fast, which makes it good for transmitting video, with low latency, across networks.  TCP has an error-checking feature which is useful for website requests, but slows down transmission.  So, to clarify:  HyperCaster output does NOT end up on the Internet.  It is a high-bitrate, high-bandwidth stream that is transmitted from one point to another.  (Now, if you want to distribute that stream to the public, ask us about the TelVue CloudCast service, which DOES put your videos on the commodity Internet.)

So what are the advantages of IP broadcast?

  • IPTV is very flexible, and in theory, infinitely scalable: That’s the attraction of IPTV for Tier 2 and 3 operators, for example, who need to be able to offer more services at reduced cost. Bolt on another switch, add another HyperCaster, and you have more channels.  PEGs, colleges, and other smaller-scale local operations need to be nimble and flexible.  SDI solutions can be expensive to implement.  You can provide the same high-quality content on IPTV without the expenses large broadcasters can incur.
  • IPTV is easily expandable.  PEG stations in particular are often limited by their analog routers – square matrices of 4×4 or 8×8 which are fixed in size.  With a network you can pick up another 48 input ports just by adding another switch.  Adding sources is as easy as adding an encoder.  Adding destinations is as easy as adding a decoder.
  • IPTV is reliable.  Networks are becoming more stable every day, and the underlying technology gets rid of the kind of signal loss you might experience with the old-fashioned composite video world, where electrical signals and cable runs could introduce hum or other degradation of the signal.  That means that schools and towns, for example,  instead of using the old iNet, can use the town’s WAN network to get their video signal back to your broadcast.  Imagine an HD signal from your town chambers travelling across the WAN to your PEG or cable facility without quality losses associated with analog modulation.  This is how major cable systems are already distributing media across the country with no signal loss: using an IP domain in their own WAN network.
  • IPTV is easier to troubleshoot because you can more rapidly identify issues.  Unlike traditional broadcast video, which doesn’t have built-in monitoring and logging, network devices have logs that tell you when something happens.  Once you send an IPTV stream into a network, you can pick it up anywhere.  In other words, you could sit at your desk and with a VLC player, and watch any available stream on that network.  Cable providers are all harnessing IPTV because they have so many channels to aggregate that the only way to manage and monitor  issues such as packet loss, video loss, video freeze, is through IP.  Many IPTV problems can be analyzed and resolved remotely, making a quicker response time possible.

Sometimes the resistance to IP conversion comes from the technicians themselves, who might be intimidated by the new skill sets that come with the transition.  But there is no stopping the convergence of broadcast and data technologies.  Anyone who follows the major broadcast trade publications must realize by now that IPTV is becoming the norm.

(Guest blogger Chris Perry is a Systems Engineer for TelVue, and in that role he often fields questions on IP broadcast and other technical matters.  Chris will be contributing regularly to the TelVue blog as these kinds of questions arise.  Keep asking!) – Editor


One Comment

  1. Katie Karow says:

    Chris Perry is the bomb and we are so lucky to have him as a resource. Thanks for keeping us updated on what is current. Broadcasting is changing so quickly, it’s difficult to run a station and keep up with technology trends. Thanks Telvue for hiring Chris. I trust and appreciate his suggestions and look forward to reading more blogs from him in the future.

    -Katie Karow
    Telluride TV

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