T1/DS1 broadband in Illinois uses two pairs of copper wire for transmission over telephone lines. An ordinary telephone line uses the DS0 transmission protocol, which carries 64 Kbit per second. A T1 line uses the DS1 protocol to combine the equivalent of 24 telephone lines for a total bandwidth of 1.536 Mbit per second.

Illinois T1 Internet providers usually offer T1 lines to private customers in DS0 fractions. However, a small business will typically use a full T1 line to connect to the Internet and a larger business may use multiple T1 lines bundled together.

There are three primary factors to consider when you compare Illinois T1 providers:

1. Prices for T1 in Illinois vary in part according to your distance from the carrier’s Point of Presence. The further you are from the carrier’s POP, the more your T1/DS1 line will cost.

2. Major carriers usually own and operate their own networks, generally resulting in the best actual transmission speeds.

3. A channel bank is necessary to separate the DS1 data stream back into the 24 DS0 data packets. This device is relatively expensive to purchase or lease and represents a substantial investment for a small business.

Action Steps
The best contacts and resources to help you get it done

Locate DS1 Internet providers in IL that sell full T1 service

Use dedicated T1 in Illinois to provide high-speed Internet access for a group of employees. These services frequently include multiple static IP addresses and email addresses under your domain name.

I recommend: Corecomm offers dedicated T1 service for businesses of all sizes and guarantees uptime of 99.5 percent. Comcast offers businesses connection speeds much faster than DSL with downloads up to 16 Mbps and uploads up to 2 Mbps.

Find a provider of high-speed Internet in Illinois that specializes in business packages

Get T1 access in Illinois from a provider that can meet your needs now and scale your requirements as your business grows.

I recommend: Verizon has a small business package specifically designed for 20 or fewer employees. EarthLink offers a symmetrical T1 business line so you can upload as fast as you download and guarantees 99.99 percent uptime.

Check out local packages from dedicated Illinois DS1 providers

The local provider connects your business to the carrier's POP. This connection is known as the local loop and represents a substantial component of a T1 line's cost.

I recommend: IVNet is based in Peru and offers businesses connections speeds up to a full T1 line. Neon Internet is in Carbondale and offers multiple options for businesses throughout southern Illinois.

Investigate some of the available Chicago broadband options

Many of the major T1 providers in Illinois are based in Chicago and offer various packages to businesses in the area.

I recommend: MSS Internet offers managed Internet service to businesses, including T1. Chicago is home to ANET, which provides full, fractional and burstable T1 lines for businesses in the Chicago area.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Illinois T1 service providers will almost always offer substantially faster access than a DSL line of the same rated speed. Providers of T1/DS1 broadband in Illinois rarely oversubscribe their services, meaning that these customers will have access to the full transmission rate of 1.544 Mbps. By contrast, the oversubscription rates for DSL lines routinely exceed 4:1.