Comcast's hybrid-fiber-coax (HFC) network was an incredible thing when it was started a decade ago, but it's showing its age and bandwidth limits. At the same time high-definition television channels are growing to become standard and filling bandwidth, users are finding Internet applications that can use up the bandwidth as well.
What really brought this problem to a head is Verizon's FIOS service, which competes against Comcast in several major markets. FIOS offers the potential of much higher bandwidth because the fiber goes all the way to the home, rather than being converted to coaxial cable for neighborhood distribution. As FIOS has offered download speeds of 20 Mbps or higher, Comcast has needed to compete and raise customer download speeds for marketing reasons. Yet Comcast's infrastructure can't handle the same kind of loads in many of those places.
The failure of Comcast's stealth bandwidth management, combined with its infrastructure limitations, has nearly forced them to implement some sort of caps. As limits go, though, these are extremely generous: 250 gigabytes per month. You could download or upload nearly two DVDs worth of data every day of the month -- 100 kilobytes per second of continuous data transfer during every single second of the month -- and not exceed this cap. So, as it stands, this cap should really affect only the true bandwidth hogs.
If this is as far as it ever goes, Comcast's bandwidth caps won't be much to complain about. However, I worry about whether Comcast and other Internet service providers will ratchet down the limits, create tiers and classes of services, or turn this into a a pay-as-you-go nightmare on the order of cell phone plans. Don't even try going there.