What is a T1 Line?
At the most fundamental level, a t1 line is the link from your companies data infrastructure to the rest of the world. A T1 line is sometimes referred to as a "dedicated service" as the service is delivered to and from the customer premises from the CO (Central Office) without combining it with other traffic.
A T1 connection is established by providing a "loop" or wire from the users premises to the CO where the service provider has equipment. Part of the cost of a T1 is the "loop charge" or the monthly rental fee for the wire that is rented from the local phone company. Once the connection reaches the CO it can access the carriers network and reach any destination.
Some more info...
The specific T1 line definition is "a digital transmission link with a signaling speed of 1.544 Mbps (1,544,000 bits per second) in both directions (download and upload)".
Basically, a T1 line is giving you 1.54 Mbps of bandwidth for you to use, whether for voice, data, or a combination of both.
In the past, a T1 line was delivered to your business on two pairs of unshielded twisted copper wires, one pair to transmit and pair to receive.
Today, a T1 line is often delivered on fiber optic lines when it is available.
You can lease a T1 line either channelized, delivered as separate voice and data channels, or unchannelized. With an unchannelized T1 line you are free to use the bandwidth as you choose to. The T1 line definition is the same for a channelized or unchannelized T1.
Channelized T1 lines are either delivered with 24 voice grade channels (voice T1) or 23 voice grade channels (PRI) with one used for signaling purposes to get features such as caller ID. If you have 10 or more phone lines, it is usually cheaper to go with a channelized T1 to replace them.
An unchannelized t1 line is best for most data applications, as well as for compressed voice, video and IP telephone (VOIP). Unchannelized T1 lines are also commonly used for high speed internet access.
T1 lines can also be used for private, leased line networking. In a private network, you might use channelized leased T1 PBXtie trunks to "tie" together your voice PBXs.
Or, you might use unchannelized T1 lines to directly connect your local area network routers or data switches, or even to tie two or more locations together. T1 lines that connect two locations to each other are typically called point to point circuits.
As you can see, even though there is really one main answer to the T1 line definition, there are still many different types of T1 Lines to choose from.
If you are looking for a T1 line and are not sure which type you need, please be sure to call us so one of our knowledgeable consultants can help you make the right choice. 
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