DS-O (Digital Signal Level 0) - A non-switched dedicated service that can be provisioned as a private line point-to-point and multi-point service. This is designed for full duplex transmission of voice, analog data and digital signals transmitting at speeds of 56 KBPS. The circuit is BI-directional and can move information in both directions. Your home telephone line is a DS-0 line. You can get 56 KBPS of data or voice through your regular phone line. The DS-0 is the "building block" of dedicated products.

DS-1 (Digital Signal Level 1) - The terms "DS-1" and "T1" mean the same thing. Most industry experts are phasing out the use of the term T1 and calling it DS-1. A DS-1 is simply 24 DS-O circuits all bundled together on one T-1 circuit. DS-1 service provides a dedicated connection from the customer premises to a long distance switch, providing the user with a single high-capacity digital circuit for voice or data applications. With a DS-1, a customer has the choice of allocating all of the DS-0 channels for
data, voice, or any combination of the two.

T1 Internet Service - For super high speed Internet, the user can allocate ALL 24 channels to data, giving them a two-way connection to the Internet at 1.544 MBPS. (Typical DSL accounts run between 128KBPS and 728KBPS). DS-1 Internet connections typically range from $300 to $1000, depending on the geographical distance between the customer and the long distance switch. Customers who use T1 data connections are typically businesses who need very high speed internet connections to transact business, communicate electronically with other offices, and who either don't qualify for DSL service or need more speed and increased reliability than DSL can offer.

T1 Voice Service - Customers with 12-24 phone lines also rely heavily on DS-1 voice service. Since there are 24 DS-O circuits bundled together on one T-1 circuit, you can have 24 phone lines connected to the long distance carrier at the same time. Any number of the total 24 channels (circuits) can be set up as:  Outbound only T1, 800-inbound only T1, BI-directional T1 and Local Service T1. T1 Voice, however, has two costs associated with it. The Local Loop and Long Distance Usage. The Local Loop is the flat fee that it costs to connect the customer to the long distance switch. This is a pass-through fee to the local phone company. The Long Distance Usage (LDU) is a separate charge in addition to the local loop. Long distance usage rates for dedicated accounts are usually 10-40% less than regular switched long distance rates.

T1 PRI Voice Service - T1 PRI Voice Service is exactly the same as T1 "regular" service, with 1 exception: only 23 channels are dedicated to voice or data. The last DS-0 channel is taken off to handle other applications, such as caller ID or a connection with the local telephone network or routing to a hold queue until 1 of the 23 channels opens up. Call Centers are the most frequent users of PRI Voice Service since they rely on the 24th line to provide caller ID.

Integrated T1 (Voice and Internet) Service - Integrated T1 service is just what the name implies: both voice and data traffic on the same T1. Since you have 24 channels (23 with PRI) to work with, you can divide up the load according to your customers need. For example, a company may have 10 phone lines. You can allocate 10 DS-0 lines for Voice, and 14 DS-0 lines for Internet.

Point to Point T1 Service - If you require constant connectivity to another office location, you should consider Point to Point T1 service. This is the same as regular T1 service, except now you have a Local Loop on 2 ends instead of just 1. This increases the cost of the monthly recurring local loop charge, but calls (or data transfer) between these two points is unlimited, with full duplex speed of T1 (1.5 MBPS).

Frame Relay Service - Frame Relay is for offices with 2 or more locations that require constant connectivity. Unlike Point-to-Point, the end-user can select sub-T1 speeds between each satellite location and the main office (or Host). This reduces cost and allows for future upgrades in speed on an as-needed basis.

Virtual Private Networks - Virtual Private Networks, also known as VPN, are a much cheaper and in many cases more practical alternative to Frame Relay. Using a VPN, companies can network their computers together from remote locations using the regular internet. VPN technology will encrypt the communications between each location so that a high level of security is present, ensuring the privacy of the virtual network.