DSL is Faster: ISDN provides two voice/data channels, each at speeds of 64 Kbps, while DSL is predominantly a data service providing up to 1.5 Mbps downstream and up to 512 kbps upstream. Business DSL offers T1-like speeds of up to 1.5 Mbps-more than 10 times faster than ISDN! DSL is "always on": ISDN is a dial-up service (like a regular telephone line) that's digital and carries both data and voice; Business DSL is "always connected"

A modem converts your computers data packets into an analogue signal (sounds a bit like a fax machine) and uses the normal telephone network to pass this to your ISP (Internet Service Provider) who then turns the signal back into data and thus enabling your computer to communicate on the Internet. ISDN also uses the telephone network to transmit data to the ISP but does not convert the data to analogue signals; instead it uses digital equipment at the exchange and on your computer.

When considering an ISDN or DSL line, know the pros and cons. Cost: ISDN through the telephone company costs an average of $60 / mo., plus a connection fee, and DSL is usually about $45 / mo. Sometimes connection fees are discounted when signing a one year term agreement (check with your provider). With ISDN, you should get 2 to 3 times faster downloads, and DSL is generally 10 - 20 times faster than dial up.

The most important difference is that we offer and guarantee your high-speed Internet access all the time at a price that is affordable. Most other services do not. In fact, it's right there in our contract agreement. While DSL (digital subscriber lines) and ISDN (integrated services digital network) connections transmit information over telephone lines at rates ranging from 32 Kbps, 128 Kbps, and much faster, these speeds are not provided to customers 24 hours a day.

If you have an existing ISDN modem, it can be used for a 144kbps DSL connection (IDSL). However, you will not be able to use the same line for DSL service. If you would like to upgrade your speed, you will need to purchase a different modem.

Generally no. There are technical and support system issues that preclude switching your service if you have ISDN or DSL with many competitive local service suppliers. Several carriers on the SmartPrice.com site provide DSL services so it may be possible to drop service with your old carrier and reestablish it with your new one.

DSL run over regular phone lines. T1's are qualified data circuits with more extensive testing and monitoring (qualified loop).

That all depends upon the telephone companies offering both services. The two services are not the same -- ISDN provides two voice channels or a 128 Kbps data channel while DSL is predominantly a data pipe providing an asymmetrical bandwidth of up to 8 Mbps downstream and 1 Mbps upstream under good conditions. However, an DSL access network will be an overlay network and therefore will not require the expensive and time-consuming switch upgrades that held ISDN back for so long.

No. DSL and Wireless services give you greater "bang for the buck", and come in speeds up to 3.0M, but you may not be able to get DSL or Wireless at your location. We recommend ISDN for locations where DSL and Wireless are not available and T-1 is not needed or affordable.

DSL is even faster than ISDN. And DSL sends data and voice over the same line so you talk on the phone while you connect to the Internet.

Your ISDN line will not support both DSL and ISDN; this means that you must have one set of wires for each service. If you want to drop ISDN service in favour of DSL you can use the wires that were installed for the ISDN line. DSL needs a few important hardware items for it to correctly work. In order to separate your voice transmissions from data over the copper line you will need to install a simple and small splitter (available from us for $ 95.00).

option is now available in the order process to migrate your ISDN line to a normal phone line, if your line is DSL suitable. Something to consider is that your ISDN line will normally have two phone numbers and two lines attached to it. When downgraded, the second line and number will be lost ? make sure you check this out fully before ordering as it cannot be readily reversed. As there is an extra step or two involved, ISDN line to DSL orders may take slightly longer.

DSL will be the cause of ISDN's demise for several reasons: - ISDN is only available in two speeds: 64 Kbps and 128 Kbps, both of which are significantly slower than most DSL connections. - ISDN sometimes offers dedicated, always on access but not always. Furthermore, ISDN is subject to additional per-minutes fees in many locations. ISDN fees can easily be in the hundreds of dollars on a monthly basis. -ISP's will charge between $30-150 a month to provide Internet access to ISDN customers.

ISDN is only available in two speeds: 64 Kbps and 128 Kbps, both of which are significantly slower than most DSL connections. ISDN is subject to additional per-minute fees in many locations. ISDN fees can easily range into the hundreds of dollars on a monthly basis. Internet service providers often charge $30-$150 a month to provide Internet access to ISDN customers.

SBC Internet Services recently joined forces with Yahoo! Inc. to bring you an enhanced high-speed Internet experience - SBC Yahoo! DSL, which combines high-speed DSL connectivity from SBC with broadband-specific content, services and applications from Yahoo!. The result is a fast, always available and custom experience. You get what you want from the Internet -- when you want it. Your high speed DSL Internet connection stays the same.

A Speed is the main reason that users are drawn to ISDN. Even with the slowest ISDN option, 64k, it is still faster than the fastest analog modems at 56k. Also, the speed is constant and does not fluctuate during a session. However, monthly rates for ISDN service are more expensive than normal POTS access, and there are additional cost features to consider.

ISDN stands for Integrated Services Digital Network. ISDN has several advantages over regular, analog modem connections.

You can use other DSL providers to access your USC e-mail but you won't have access to USC restricted resources, such as directory pages and servers.