Some Class Qs on IP


Nothing like teaching a class about the transition to everything over IP (Internet protocol) to keep you on your toes, translation- wise.

What’s top of mind about IP in a classroom full of cable people at this moment in time? For starters, that skinny little upstream path and whether Comcast is doing something different with it, given its work on video-Skyping via the TV.

Lots of questions, too, about what all ultimately goes into “the cloud.”

And, my personal favorite, because it’s easiest to answer: What is VoLTE?

Answer: Voice Over Long-Term Evolution, where “LTE” is that get-funky mobile euphemism for wireless broadband. LTE was developed for broadband and is oriented for IP-based data services.

So, putting voice over LTE isn’t as much of a no-brainer as you’d think, even though mobile as an industry grew up on voice as its bread and butter.

From a consumer angle, Comcast’s work with Skype is imaginable: Wave to the nieces from a perch in front of the TV, instead of in front of the laptop. As for Comcast’s upstream signal boundaries,they’re no different than the rest of the industry: a mean little swish of spectrum located between 5-42 MHz.

MSOs historically and deliberately haven’t attempted to stuff video upstream. Why? Not enough room. Will the blobbish-ness of video-Skyping clog it up?

According to the engine-room talent working on it, there are two things to keep in mind here. First, there’s a beginning and an end to a phone call. Unlike TV, you don’t usually leave the phone on or open after you’ve said goodbye.

Two, the signaling and codecs involved are designed to be mindful of bandwidth. This means that Skype in the upstream is not like that swell surveillance camera on sale from Acme Camera, which only does full-motion JPEG at 5.5 Mbps upstream (because it’s cheaper! And bandwidth is free!).

About the cloud, and what all goes up there: maybe not everything, but close.

Remember that cable innately is a cloud - an intelligent network that relays entertainment, information and communications back and forth to homes. Watch for cloud storage (think network DVR), and cloud guide (think iPad app), and the business logic and databases of “the back office,” in the cloud. Identity management, parental controls. Voice mail and email already sit in the cloud for the most part.

We are entering the kitchen sink phase, friends, for clouds and gateways. This is a transition, a marriage of households. That means for some period of time, you’ll either need two of everything, or have three of the thing you don’t need.

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