Cable broadband, once thought to be a low-end networking option, has been quietly getting a major technological overhaul that makes it competitive with fiber optic bandwidth for many business applications. Companies that once wouldn’t consider cable for more than a backup connection now find the combination of high performance and low cost too compelling to ignore. Let’s take a look at what’s happened behind the scenes and what options cable offers now and in the near future.
Magic #1: The HFC Cable Plant
When cable started out as cable television, it was little more than a set of really tall antennas feeding tuners and distribution amps at the “head end” to create an equivalent to what you would get off the air…if you could get such good reception. The all-analog collection of signals got boosted and distributed all over town, but what came out the connector on your TV was very much a more potent version of OTA (Over The Air) Television.
Time passes and the handful of OTA channels were augmented by dozens and dozens of non-broadcast channels delivered via satellite to that same head end. These “cable channels” quickly ate up all the capacity of the big coaxial cables that fed the little coax cables that fed the TVs. Cable companies launched rebuilding programs to increase capacity… but not by doing more of the same. Instead, they strung new fiber optic bundles and then connected their existing delivery cables to the new fiber optic trunk lines. This combination is called HFC or Hybrid Fiber-Coax.
The HFC system, combined with all-digital transmission creates a huge increase in capacity to accommodate a hundred or more TV channels with extras that can be used to deliver Internet broadband over the same cable. Note that the cable that connects to your TV or modem looks the same as the old analog cable. It is. But, it only needs to run a short distance before it hooks up with the enormous capacity fiber optic network. You get the best of both worlds… high capacity fiber to the curb plus inexpensive passive coaxial cable for termination of the service in the home or business.
Magic #2: DOCSIS Broadband
DOCSIS is a cable broadband standard that stands for Data Over Cable Service Interface Specification. It was created specifically for cable companies to be able to also deliver Internet. To do that, DOCSIS signals fit into low frequency spectrum not used for TV signals and spare standard television channels on the cable.
The first version, DOCSIS 1.0 was released about the same time as the Internet was taking off, 1997, followed by version 1.1 in 1999. A faster version 2.0 came out in 2001. That’s the one most of us cut our broadband teeth on, after finally running out of patience with dial-up telephone Internet. A few years ago you probably upgraded to a DOCSIS 3.0 modem, which brings the system up to today’s standards.
DOCSIS 3.0 makes cable a serious contender for business broadband service. It supports the latest Internet Protocol version 6 (IPV6) and has a downstream (download) capacity of 1 Gbps with an upstream (upload) capacity of 100 Mbps. In practice, may users run something like 25 to 75 Mbps down and 5 to 7 Mbps up.
Magic #3 DOCSIS 3.1 Thinks It’s Fiber
The newest technical upgrade to HFC systems is called DOCSIS 3.1. It sounds like an incremental change, but the performance jump is enormous. DOCSIS 3.1 offers downstream speeds of 10 Gbps max with upstream of 1 to 2 Gbps max. Cable bandwidth is called asymmetrical because the download speeds are typically 10x the upload speeds. A further enhancement, not yet deployed, is Full Duplex DOCSIS 3.1 that will offer 10 Gbps upload and 10 Gbps download. That’s pretty much the high end of what you’ll get with fiber or by leasing a fiber optic wavelength… at a fraction of the cost.
The Appeal of High Speed Cable Broadband
Cable broadband is the most compelling Internet access for any business that can get it. You do need to be in a location with cable already running down the street, but you stand a much better chance of having cable available than fiber. It’s mostly out in rural areas that neither fiber or cable are available and high speed satellite becomes the service of choice.
The big appeal of cable is how much bandwidth you get for the money. You’ll easily pay 5x to 10x as much for SONET or Ethernet fiber optic services. In some cases, that extra expense is worth it. Cable bandwidth is shared among the pool of users, while higher priced telecom services have dedicated bandwidth for your use only. SONET and Ethernet over Fiber services are symmetrical and come with service level agreements that guarantee a certain level of performance and availability at all times.
If your business is running a server farm in-house or distributing large software packages or video streams, you’ll need a high speed dedicated service. But, if your business uses cloud services, collocated hosting, or has simple needs for web browsing and email, cable broadband may have all the capacity you can use and at bargain rates. You should at least give it consideration before you sign an expensive lease. Our expert consultants can help you make the best decision based on the particular needs of your business. Compare DOCSIS cable with other copper, fiber and satellite bandwidth options available for your business location.
