Thursday, November 03, 2005

Fractional DS3 Applications

The most common high reliability broadband connection for business is the T1 line. T1 lines are available most everywhere, are affordable for most small and medium businesses, and come in a variety of options that include PBX telephone lines, dedicated Internet access, point to point electronic data interchange and a combination of voice and data called Integrated T1. The only real problem with T1 service is that you might outgrow it.

T1 connections provide a bandwidth of 1.5 Mbps full duplex, also called symmetrical for Internet service. You get 1.5 Mbps in both directions. You can get fractional T1 service if you don't need the full 1.5 Mbps. But what if you need more?

T1 service is perfect for most point of sale, telephone system and Internet access needs of small businesses and some medium businesses. Larger bandwidths are needed when business volume expands or the number of users grows beyond a dozen or two. Larger bandwidths are also needed for throughput demanding applications such as CAD drawing transfers, movie production, television program distribution, medical data transmission and enterprise VoIP.

The next higher telecom standard is the T3 line, also called DS3 service. T3 isn't three times the capacity of T1, like you might suspect. Instead, it is 28 times the capacity of a T1 line or 45 Mbps. The cost is substantially greater due to the increased bandwidth and differences in the technology needed to provision T3 lines. DS3 service is most often provided over fiber optic cables versus common twisted pair copper wires used for T1. In some cases, especially within a carrier's facility, T3 can be provisioned over coaxial cable.

T3 has the bandwidth needed to support many Internet service providers or off-site backup needs of corporations. It is commonly used by colleges and school systems to provide Internet access for faculty and students. A T3 line can transport up to 672 simultaneous telephone calls or carry two channels of HDTV television programming using MPEG-2 compression. That's a substantial bandwidth, but what if you don't need or want to pay for quite that much?

When you need bandwidth between 1.5 Mbps and 45 Mbps, you need fractional DS3. You can get fractional DS3 in just about any bandwidth your application requires, including 5, 10, 15, 20, 25, 30, 35, 40 Mbps and other increments. Like other WAN bandwidth, the monthly price you pay is based on the bandwidth you receive.

There are a couple of was to implement fractional DS3 service. One is to run a coaxial T3 line or DS3 over fiber optic cable, but throttle the bandwidth down to a fraction of the full DS3 limit of 45 Mbps. That works fine if it is feasible to provision coaxial or fiber optic cable to your building. Another option is to bond T1 lines together to gain multiples of 1.5 Mbps, such as 3, 4.5, 6, 7.5, or 9 Mbps. Each T1 line requires a pair of copper telephone wires, but even remote business locations often have bundled cables with many pairs available.

Another related service you should be aware of is WAN Ethernet. You're familiar with Ethernet in your local area network. Now it is commonly offered for connections beyond your premises. Ethernet runs at 10 Mbps, which fits the definition of fractional DS3 service. In practice Ethernet service may be delivered over a TDM (time division multiplexing) line such as T3, or on a native IP network which is Ethernet end to end.

Do you have an application that needs more bandwidth at the most competitive price? Let our team of experts find the right bandwidth in the right format at the best price for your business. Tell us about your need and we'll get right on it.

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

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