T1

T1 or Trunk Level 1, is a digital transmission link with a total signaling speed of 1.544 Mbps. Since its development in 1957 by AT&T's Bell Labs, it has become the building block of dedicated voice and data service in North America. T1, also know as DS1, is part of a progression of digital transmission pipes - a hierarchy known generically as DS, or Digital Signal Level.

T1 service can be delivered to the end user in either a channelized format or an unchannelized raw bit stream. North American carriers typically deliver T1 split into 24 56/64kbps channels. These channels can be used to transmit voice (typically one conversation per channel) or data across a network. A T1 alone provides no services to a location, only a means of getting those services from the network into your office. For example, should a location require a dedicated T1 for internet access, you would have to pay both the T1 charge (commonly known as the "loop" charge) and the Internet access port charge; this is the cost of the throughput into the Internet. These charges often make the cost of a Trunk Level 1 line considerably higher than a DSL line.

What is a Full T1 Connection?

When a carrier gives you the option of purchasing a full T1, you can get the full 1.544Mbps circuit unchannelized direct into the Internet (or Frame Network, or Point-to-Point); also known as a clear channel T1. A Fractional T1 is a channelized T1 with only some of the channels turned on. Fractionals are normally priced in terms of Kbps. For example you can get 384kbps, 512kbps or 768kbps from most carriers. However, given the cost of provisioning, you may be better off paying a couple hundred dollars extra for the full line. Fractional T1

What is an Intergrated T1?

Because T1s can be broken out into channels, voice and data can run side by side on the same circuit. They require a device to convert the signaling from that used on the T1 into signaling that can be used by the phone, the equipment, or router. The technical name for this process is multiplexing and the equipment required is called a multiplexer; but it is known more commonly as a channel bank, CSU/DSU or T1 card. In the case of an intergrated one, the service can be run from the phone company's jack into the channel bank where the voice service is terminated and a jack for the data service is located. The benefits of using an intergrated version include lower rates for long distance, additional lines for long distance and toll free calling and the ability to bundle your data and phone costs on the same bill and same circuit. Nearly all providers are capable of offering intergrated voice and data products, some can even bundle local, long distance and data all on the same circuit. If you are looking for more information on Intergrated T1s or need to price service for your location, fill out our quote form and Business T1, T3 & DSL Line will provide you with prices from multiple providers within two business days.

Are Frame Relay, VPN, Dedicated Internet and T1 the same?

Frame Relay, VPN and Dedicated Internet Access all use T1 connections to make the respective service possible, but they are not the same. By itself, Trunk Level 1 service is nearly useless. It takes a standard or protocol like Frame Relay or VPN to provide data transport over a Wide Area Network.

The four most common uses of a T1 line include: