Glen Hardin of Time Warner Cable recently wrote a comprehensive (and fabulous) article for Cable360 on the 2008 ruling in favor of Cablevision’s right to offer network-based DVR services. In it he uses the more precise term Remote-Storage DVR (RS-DVR) rather than Network DVR (nDVR) to describe the technology Cablevision has proposed. Is the difference in jargon critical? Actually, yes. Even if you have very little interest in the technical details, there are practical ramifications to the fact that Cablevision may one day soon launch RS-DVR rather than true nDVR services.
Very briefly, nDVR refers to a service where a program can be recorded and stored in the cable network and then accessed by any subscriber. In contrast, RS-DVR refers to a service where any subscriber can record a show and store it on the cable network, but that stored programming is only available to the person who recorded it. For legal reasons, even if two people want to record the same show, it has be recorded twice, and each recording discretely stored.
RS-DVR is legally pragmatic, but technically it represents a series of trade-offs. Instead of set-tops that need loads of storage space, you end up with mammoth amounts of space needed on the network. Discrete storage of each recording also means that there’s no way to cache content for more efficient delivery of popular programming. And finally, the fact that each recording requires its own video ingest means that video servers need significantly more ingest capacity than they currently have.
There’s a lot of potential in network-based DVR services, even the somewhat hamstrung approach of RS-DVR. (More storage options, everything on-demand, new interface options for management of recordings) However, the technical burdens mean that RS-DVR won’t necessarily provide subscriber cost savings early on as some might expect. Also, I have to wonder at how smoothly RS-DVR can be implemented in the short term given the new technical requirements. I expect there will be kinks even once the service finally becomes available from a service provider near you.