Om:Yes, Gillmor:No ... Comcast's Data Transfer Cap

Om Malik nailed it at the end of one his posts on the 250GB cap. He lists Comcast's stilted usage examples for email, music, etc., and asks "How many HD movies will fit under the cap?"

That's the right question, but not because he is worried he'll bump the cap watching video.

The reason it's the right question is that the cap has more to do with Comcast's long-term business plans -- and the cable/telco industry's plans -- than about slapping down a handful of network hogs.

One fact before we continue. As I've written before, while everyone squabbled over BlueRay or HDDVD, the filesharing world settled on the x264 implementation and a container format for it. In that compressed format, a high-def film averages 10-15 GB.

But here's the real deal:

Comcast's cable TV and on-demand video business competes directly with Internet video (both legal and gray-market). By making the cap high enough that it won't immediately impact YouTube watchers but -- over time -- will put a serious dent in customers' ability to get HD video over the Internet, Comcast is simply crippling one product so that customers will have to buy another product from them. Don't even think about mentioning broadband competition -- if you define competition as more than one entity offering substitutable goods (i.e. similar bandwidth, QoS, etc), then most of the U.S. has zero competition.

The 250GB cap is a way to push customers to buy the same content twice. To be specific, you'll pay to see a movie broadcast on cable TV in HD, and then pay again for some special plan that lets you watch the same content later on Hulu. Or you'll pay for Comcast "on-demand" to watch a show on your TV. But if you want to place-shift that show to your laptop or the gym (on your phone), you'll have to pay to get enough headroom to download the same video.

This move is not just about trying to squeeze out more money. It's yet another attempt by network operators to neglect their core business and instead try to get into a content business, so they can do two things badly instead of just one.

Meanwhile, Steve Gillmor writes that bandwidth caps will mean the end of BitTorrent downloading and a shift to streaming. Steve's a smart guy, but streaming is one of those perennial non-trends like speech recognition and thin-client computing. It's only conceivable to someone who has a computer connected to their TV or who lives on their laptop.

Having played a key role in several home-entertainment / media-tech startups, two of which have been successfully acquired, I feel confident saying streaming is only a little piece of a solution. For the foreseeable future, streaming will never be more than that. It neglects too many consumer needs and desires, is too inflexible, and is too warped by DRM and platform-lock-in issues.

Moreover, the latest round of DRM around HDMI and high-def media playback in general means that even in-home "streaming" -- i.e., from a PC to a TV or from one PC to another -- is facing setbacks just as Joe tech-savvy consumer finally starts to realize how to use a home server or network attached hard drive to get and watch shows.

And the set-top boxes, increasingly tied in tightly with content delivery (Comcast DVR, DirecTV TiVo expiring your pay-per-view movies, etc.) are more closed than ever. Instead of encouraging an ecosystem of streaming, they force customers into an ecosystem of downloading.

I think we'll see more people gaming the 250GB cap ... using scheduling software so they can maximize the utility of the 250GB and hoard downloads. Not to mention leaving the torrent client running so that every time I visit someone else's network -- an office, a coffeeshop, etc. -- I'll keep the downloads slowly but surely coming in.

One final note: the marginal cost of moving a kb of data around a big network -- that is, the cost of the power and cooling for the switches and the amortized cost of the cables and gear and ops guys divided over their lifetime data transfer -- is more or less zero when the network isn't already near peak bandwidth somewhere. So even if there is a problem, the volume-based cap is the answer to a different problem.

Tips: Cable Modem Signal Troubleshooting

I've had a few problems with fluctuating signal levels on my cable modem, which result in losing connectivity for a period of time. If you have a cable modem and the connection has ever been flaky for no apparent reason, you might be able to use a few tips I've picked up.

First, most cable modems have an internal management/monitoring system you can use to see what's going on, and it's conveniently exposed via HTTP so you can look at it with your browser.

This web page has a great collection of information on accessing the modem status and what numbers and error messages to look for. This may sound obvious, but download all of the info before you have an outage unless you have a redundant connection. (Also, don't be scared off by the old dates on the page ... most newer models have the same interfaces, and of course DOCSIS is a standard so it doesn't change year to year).

The modem typically listens on 192.168.100.1. So if you have a router (e.g. a WiFi access point) between your PC and modem, you may need to adjust the subnets or routing, or remove it, because this subnet may be downstream/local/wrong-side-o-the-box for you. If subnets and routing aren't your thing, the easiest alternative is to unhook the router and connect directly to the modem.

With cable modems, it's not just an issue of having a "strong enough" signal -- the signal has to be consistent within a certain band, because the modem determines its uplink transmit power level based on the downstream level it observes. In other words, if the downstream level comes in too strong, then the modem will reduce its upstream power in response, and you can lose connectivity because of that.

If you've had some issues, you see signal fluctuations, and your cable operator doesn't have any reports of problems (their system can remotely observe other people in your area), here are a couple of remediation steps to try:

First, isolate the cable modem on your wiring -- meaning unhook other devices, TVs, DVRs, etc., which might be on your line. Clearly not a long-term solution, but if this makes a difference then you'll have info that will help if and when you do need the cable company to make adjustments.

If that doesn't make a help, follow the cable line (assuming you can get to it) from the modem all the way back to where it comes into your house. Remove any unneeded splitters, barrel connectors, 20m tangles of  coax, etc. To the extent that you do need these parts, they should be ideally be 5GHz capable (marked that way right on the device). If you have older ones that say, e.g., 1000MHz, replace them with newer ones.

Splitters and the like are not normally weatherproofed, and apparently (I have no proper data to support this, but technicians have told me), they show deterioration after a few years of exposure to heat, cold, condensation, etc. in basements and crawlspaces -- enough to cause a high-frequency signal to get flaky. And they can end up producing effects that vary with temperature.

Last, on my line, a technician also chopped out the connectors where the cable company's own line transitions to the house wiring, put new connectors on both sides, and hooked it back together. If you want to make this swap, or replace any of your connectors (as opposed to parts that the connectors attach to, like splitters), you'll need a coax tool for cutting and stripping the wire and then crimping on a new connector.

These primitive coax tricks won't solve all problems (even in my own installation, these changes resolved maybe 85% of the trouble) but they may make a difference and, at the least, they'll remove a bunch of unknowns from your equation.