Tuesday, April 05, 2005

What Is Dedicated Internet Service?

We tend to put Internet connections into two categories. One is dial-up Internet service using a standard 56K modem. The other is broadband Internet delivered via DSL, cable modem, WiFi hotspot or wireless point to multipoint distribution. But how about a third alternative that is more reliable and faster than the others, perhaps with almost unlimited speed. That's dedicated Internet service.

But wait a second? My current Internet service is already dedicated, right? I mean, I'm the only one logging into it. Yeah, right. If you look at what's plugged into your modem and there's only one wire to your computer, your modem is indeed dedicated. Your internet service isn't by a long shot. Somewhere out of sight, probably at the local telephone, cable or wireless office, you are a mere one of many connected to the same Internet service. For DSL the device that divvies up the service is called a DSLAM or Digital Subscriber Line Access Multiplexer. The key word is Multiplexer. Any circuit that is multiplexed is shared.

The DSLAM at the telephone company office or its equivalent, the CMTS or Cable Modem Termination Service at the cable TV head end, takes a single broadband trunk line from an Internet Service Provider and splits out the bandwidth among dozens, hundreds or even thousands of customers. The theory behind this is that not all subscribers will be online at all times, even if the connection is always available. Most Internet users spend the majority of their time reading or writing email, looking at the web pages they have visited, and occasionally downloading software, music or streaming audio. While you're connection is idling, someone else can use the bandwidth to load another web page. In fact, during large parts of the day many computers will actually be shut off.

Now spread out this behavior over thousands of subscribers and you'll know statistically what the average bandwidth demand is. That's how big a line you should have to feed the DSLAM or CMTS. But broadband providers often oversubscribe their connections so that during busy times the connections can slow almost to dial-up speeds while in the wee hours you can get several megabits per second on download. If things bog down too much, the provider can always install a bigger pipe to the ISP.

Now, how would you like to have a direct connection from your router all the way to the Internet Service Provider? No DSLAM, no CMTS, no sharing. Well, you can share it within your office or with patrons of your business through a WiFi hotspot. But that's your choice. You're not at the whims of bandwidth hogs who are constantly downloading something or other or always streaming audio and even video at broadband rates. Yes, ISPs can oversubscribe their backbone connections to the actual Internet. The better ones will give you the bandwidth you are paying for.

The basic dedicated Internet service is delivered on a T1 line, a fractional T1 line or an even faster trunk. T1 runs at 1.5 Mbps, about the same as the advertised speeds for many DSL and cable Internet services. But since that 1.5 Mbps runs directly to the ISP, regardless of distance, it will generally perform both faster and more consistently than other broadband Internet services. A T1 line also comes with a service level agreement that results in more reliable service. If T1 isn't fast enough to support your organization's Internet access need or if you are transmitting high bandwidth video, you can step up to a T3 line at 45 Mbps or even an OC3 optical carrier at 155 Mbps. There are even faster connections, but you won't need them unless you are an Internet or applications service provider yourself.

Get a complimentary quote on T1 dedicated Internet service for serious business applications (T1 prices start at $200 to $400 a month) from Telexplainer.

Click to check pricing and features or get support from a Telarus product specialist.

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