Q > How does DSL work?

A > Traditional phone service (sometimes called "Plain Old Telephone Service" or POTS) connects your home or business to a telephone company office over copper wires that are wound around each other and called a twisted pair. Traditional phone service was created to let you exchange voice information with other phone users and the type of signal used for this kind of transmission is called an analog signal. An analog signal takes a carrier wave of a certain frequency and adds information to it by varying the frequency or the amplitude (strength) of the signal.

Because analog transmission only uses a small portion of the available amount of information that could be transmitted over copper wires, the maximum amount of data that you can receive using ordinary modems is about 56 Kbps (thousands of bits per second). (With ISDN, which one might think of as a limited precursor to DSL, you can receive up to 128 Kbps.) The ability of your computer to receive information is constrained by the fact that the analog transmission is a bandwidth bottleneck.

Digital Subscriber Line is a technology that assumes digital data does not require changing into analog form and back. Digital data is transmitted to your computer directly as digital data and this allows the phone company to use a much wider bandwidth for transmitting it to you.

Q > Why should I consider using DSL?

A > DSL uses the already existing copper infrastructure thus maximizing previous investments. DSL, since it is a dedicated "per subscriber" service, provides built-in security.

Q > What's the difference between DSL modems and cable modems?

A > The use of standard phone lines affords DSL a number of advantages such as:

• Speed - DSL service enables full use of the phone line's bandwidth, whereas cable modem users will enjoy only a fraction of the cable modem's potential speed. As more cable modem users go online, everyone's throughput will be lower.
• Availability - Copper phone lines are installed in almost every home and business worldwide. Coaxial cable is not.
• Security - Since single cable modems operate on a shared line, security becomes an issue that is not present with DSL.

Q > What are commonly used DSL terms?

A > Some commonly used DSL terms are:

• ADSL (Asymmetric Digital Subscriber Line): 1.5Mbps/64Kbps-384Kbps upstream
• HDSL (High-bitrate Digital Subscriber Line): 1.5Mbps/1.5Mbps upstream
• IDSL (Integrated Digital Subscriber Line): 144Kbps/144Kbps upstream
• SDSL (Single-line Digital Subscriber Line): 1.5Mbps/1.5Mbps upstream
• VDSL (Very high-bitrate Digital Subscriber Line): 13Mbps- 52Mbps/1.5Mbps-2.3Mbps upstream
• RDSL (Rate Adaptive Digital Subscriber Line): various speeds
• CLEC - Competitive Local Exchange Carrier: one of the new U.S. telephone access and service providers that have grown out of the recent U.S. deregulation of telecommunications.
• LEC - Local Exchange Carrier (your local phone company): LECs own the central offices and the local telephone lines that run from these offices to businesses and residences in a specific geographical area.
• Dedicated Line - A transmission circuit installed between two sites of a private network and connected or available at all times.
• Dial-up - A type of communication that is established by a switched circuit connection using the telephone network and is only connected when the user dials in to a network.
• Fractional T1 - A communications service that provides the user with some portion of a T1 circuit that has been divided into 24 separate 64 Kbps channels.
• Packet - A logical grouping of information that includes a header and usually user data. It's a continuous sequence of binary digits of information which is switched through the network as an integral unit.
• Packet Switched Network - A network in which data is transmitted in units called packets. The packets can be routed individually over Epoch's network connection and reassembled to provide a complete message at the destination.
• Twisted Pair - Cable consisting of two 18 to 24 AWG (American Wire Gauge) solid copper strands twisted around each other. The twisting provides a measure of protection from radio-frequency interference.

Q > What is a DSL Circuit?

A > The DSL circuit installation is not much different than a regular phone line installation. Just like a regular phone line, the DSL circuit terminates at what is called the Minimum Point of Entry, or MPOE. This is usually a punchdown block in a wiring closet (for most businesses). If the customer needs the circuit extended, D&E Jazzd will provide inside wiring from the MPOE to a customer specified location. An RJ45 outlet is placed at the end of the inside wiring run.

Q > Is Inside Wiring Free?

A > No. There will be an additional charge if additional wiring is necessary.

Q > Can I use an existing phone line with DSL?

A > Yes. If the existing phone line is up to standard, there should be no issue. Most small- to medium-sized businesses have many pre-wired telephone lines. Therefore, you probably already have the lines necessary to install a DSL connection without additional wiring.