DSL Types
SDSL ADSL RADSL IDSL HDSL VDSL

DSL technology supplies the necessary bandwidth for applications such as high-speed access to the Internet, dedicated Internet connectivity, remote Local Area Network (LAN) access, video conferencing, and Virtual Private Networks, just to name a few.

DSL is a broadband digital connection made directly to your premises using existing copper telephone lines. The DSL modem maintains a digital link from your business to our network. This modem can drive ordinary telephone lines at speeds far beyond conventional dial-up modems. The modem plugs into your existing local area network or can be attached to a PC using a special cable.

You may have seen the term xDSL. There are many varieties of DSL technology. DSL.net provides the optimal Business-to-Business solution, SDSL and, home office or high speed home user, ADSL

SDSL - Symmetric Digital Subscriber Line - This technology provides the same bandwidth in both directions, upstream and downstream. That means whether you're uploading or downloading information, you have the same high-quality performance. SDSL provides transmission speeds within a T1/E1 range, of up to 1.5 Mbps at a maximum range of 12,000 - 18,000 feet from a central office, over a single-pair copper wire. This option is ideal for small- and medium-sized businesses that have an equal need to download and upload data over the Internet.

ADSL - Asymmetric Digital Subscriber Line is the form of DSL that will become most familiar to home and small business users. ADSL is called "asymmetric" because most of its two-way or duplex bandwidth is devoted to the downstream direction, sending data to the user. Only a small portion of bandwidth is available for upstream or user-interaction messages. However, most Internet and especially graphics- or multi-media intensive Web data need lots of downstream bandwidth, but user requests and responses are small and require little upstream bandwidth. Using ADSL, up to 7.1 megabits per second of data can be sent downstream and up to 640 Kbps upstream. The high downstream bandwidth means that your telephone line will be able to bring motion video, audio, and 3-D pics to your computer or hooked-in TV set. In addition, a small portion of the downstream bandwidth can be devoted to voice rather data, and you can hold phone conversations without requiring a separate line. Unlike a similar service over your cable TV line, using ADSL, you won't be competing for bandwidth with neighbors in your area. In many cases, your existing telephone lines will work with ADSL however, in some areas, they may need upgrading.

There are other varieties of digital subscriber lines that we will briefly describe.

RADSL - Rate Adaptive Digital Subscriber Line - This technology automatically adjusts the access speed based upon the condition of the line.

IDSL - ISDN Digital Subscriber Line - This technology is symmetrical, similar to SDSL, but operates at slower speeds and longer distances.

HDSL - High-Data-Rate Digital Subscriber Line - This technology is symmetrical, but is mainly deployed for PBX over a T-1 line.

VDSL- Very-High-Rate Digital Subscriber Line - This is a high-speed technology, but has a very limited range.