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Is network DVR ready for prime time?

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Like culture and traditions, copyright laws are unique to each country. When these laws are restrictive—only allowing storage of private copies for network DVR—it can be a big headache for multinational content providers, as well as being too costly for service providers.

So how does this play out in real life?

Under the private copy model, when multiple users are recording the same TV program, the service provider needs to store one copy for each and every user in the network. This copyright model creates two challenges for service providers:

  1. Storage challenge: the storage becomes expensive, not just because of the volume needed, but also because of the need to simultaneously read (stream) and write recordings. This requires high performance and scalable storage with low latency. Typically this runs at a pricey 1$+ per gigabyte.
  2. Network challenge: since each recorded asset is unique, there are no caching benefits. Even if multiple users living in the same area are watching the same recorded TV program, one stream for each user has to be sent from central storage across the entire network. The result? Huge surges in traffic for popular content at peak viewing times.

These storage and network problems are throttling the potential of network DVR. Although end users are enjoying the benefits of network DVR, it’s very costly for operators when compared to the shared copy model. Plus, their monetization opportunities (multiscreen access of recordings, increased storage capacity, multiple tuners, and so on) don’t make up for these shortfalls.

What’s the way out?

Once again the answer is innovation—in this case innovative network architecture. While respecting the content rights framework, content delivery network (CDN)-assisted private copy removes these two problems. Using this architecture, a single copy for each user is maintained in tiered storage made of a fast tier and an archive.

When multiple users record the same TV program, the content is cached once in the fast tier and unique copies (one per user) are created in the archive. When users want to play a recording, they send a request by pressing ‘play’. At the time of playback, this request is unique to the user and to their copy located in the archive. A scheduler intercepts the request and maps their copy to the cached asset. If the content is popular, the asset can be streamed from a server located close by.

This results in two significant benefits. It lowers the performance requirements of the archive. This reduces costs by a staggering 75% compared to high-performance storage used in a private copy network DVR. At the same time, distributed caching also saves a great deal on transit traffic within the network.

CDN-assisted private copy is a game changer for network DVR

This is especially the case in North America and in some European countries where copyright laws only allow for private copy. While complying with local legislation, this new architecture enables the cost-effective deployment of network DVR.

Looking ahead, CDN-assisted private copy also provides for a simple migration to shared copy when copyright laws or content agreements evolve. It’s as straight-forward as removing the archive storage and disabling certain features within the CDN. And, because cloud DVR allows operators and content providers to directly control features, this can be done channel by channel to allow a mixture of private and shared copy.

So how is network DVR adoption going so far?

As of early September, Alcatel-Lucent has deployed 30 petabytes of storage capacity for network DVR operating in 12 countries with 8 operators. Located in countries with more permissive copyright laws, Swisscom and Telefonica are leading the way with cloud-based recordings. They’re offering 1000 and 350 hours of recordings respectively to their subscribers. Just imagine the pent-up demand for capacity if restrictive digital rights were not a blocking factor in North America and elsewhere in Europe.

Thanks to innovations like CDN-assisted private copy, consumers and content providers are poised to push network DVR into prime time.

related material

IP Video solution page Cloud DVR solution page

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Roland Mestric

About Roland Mestric

Roland Mestric is head of marketing for IP/optical networks automation at Nokia. In this role, Roland is responsible for defining and executing global marketing programs for the management and control of transport networks. Roland has 20 years of experience in multimedia and next-generation networks in pre-sales and solutions marketing roles with Nokia and Alcatel-Lucent.

Tweet me at @RolandMestric

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