We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is IDSL?

By R. Kayne
Updated May 16, 2024
Our promise to you
EasyTechJunkie is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At EasyTechJunkie, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

ISDL is a hybrid of ISDN and DSL (Digital Subscriber Line) technology that uses a little of each to deliver a service that is slightly faster than ISDN, but significantly slower than most DSL services. A person might opt for ISDL if standard DSL service is not available in his or her area.

Standard ISDN (Integrated Services Digital Network) service uses existing copper telephone lines to deliver data transfer speeds up to 128 kilobits per second (kbps). It also provides voice channels for telephone and fax, making it superior to standard dial-up, which cannot share an Internet connection with a telephone or external fax machine. Standard dial-up is also much slower than ISDN at about 53 kbps. However, ISDN is still a dial-up service, as opposed to an "always on" service like DSL.

IDSL uses the same technology as ISDN except that it routes the signals through different equipment at the phone company or Telco. While ISDN uses the standard switching equipment, IDSL uses DSL-like equipment. The difference is two-fold: an increase in speed to 144 kbps, and an "always on" connection.

IDSL can be expensive to set up, but may be worth it to businesses or individuals that require faster service without the option of DSL. One of the advantages of IDSL over DSL is that the former is not limited by distance from the Telco. To be a DSL subscriber, the client must be within the limit of 18,000 wire-feet (5,486 wire-meters) from the Telco hub. If the residence or business falls at the outer limits of this range, the maximum speed of the DSL connection will be significantly reduced and signal quality will not be optimal. The closer to the Telco hub, the better the DSL service. IDSL does not have this limitation, allowing clients at further distances to have an "always on" connection.

One drawback of IDSL is that it requires its own telephone line for the IDSL service, while a second line provides phone services. This makes it more expensive than ISDN.

Ascend Communications developed IDSL technology. If you think it might be the right solution for your needs, contact your local telephone company to ask about ISDN or IDSL services in your area.

EasyTechJunkie is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
By ginSoul — On Jun 26, 2011

I have IDSL and I wanted everyone to know that you don’t always need to purchase a second phone line if you have IDSL. Some service providers (like the one I’m a customer of) give you a splitter when they send you your IDSL modem. The splitter plugs into the phone jack on your wall. There’s one jack on the splitter for your Internet connection, and one for your phone line. That way, you can be on the Internet and use your phone at the same time!

By Animalz — On Jun 23, 2011

@SailorJerry – Yes DSL is pretty slow, but it still has better bandwidth than dialup. The problem with cable is that you have to get a physical cable installed in your house in order to receive cable Internet.

My old apartment had cabling already installed, so it was a cinch to get cable Internet service there. My new place doesn’t have cabling, and the landlord won’t let me install any. So, I have ADSL simply because it uses the pre-existing phone lines and I have no other options.

By omgnotagain — On Jun 20, 2011

@anon19301 – Did you mean IDSL, not ISDL? AT&T’s website doesn’t say anything about them offering ISDL service. I have At&T and I’m pretty sure they only offer a variety of DSL packages.

To answer your question, IDSL is slower than ADSL. ADSL has an internet speed of up to 8 megabits per second. That’s over eight times faster than IDSL. Most people don’t need a really fast connection, but if you do a lot of online gaming or watch high definition movies online, you might want to get ADSL. Also, if you upload a lot of large files, you’d be better off with ADSL.

I have a slow IDSL connection (it’s all I can afford at the moment), and it works for me. The only problem I have is that watching online videos can be a pain. The movies can’t download fast enough, so and they pause every ten minutes. If you can afford it, I’d go with ADSL, just because the fast download speeds make Internet use so much easier.

By SailorJerry — On Jun 20, 2011

What are the advantages of going with DSL internet? Isn't it pretty much the slowest broadband option?

I had DSL at my old house. It was one of the more reliable services I've had (the only problem we had, I think, turned out to be our modem!) but it was definitely the slowest. When we moved and had cable internet again, we really noticed a difference. Our current cable internet is pretty wonky, but our last provider was rock-solid.

By anon19510 — On Oct 13, 2008

As the article states, ISDL is typically slower than ADSL. Stick with ADSL. People generally only get ISDL if ADSL is not available.

By anon19301 — On Oct 09, 2008

what is the difference between a ISDL line and a ADSL line???>... we are being quoted both from AT&T

EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.

EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.