Internet Service Provider (ISP)

What exactly does an internet service provider do?

An image representing the internet and the traffic it produces

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An internet service provider (ISP) provides access to the internet. This access can be through a cable, DSL, or dial-up connection. All internet-connected devices run each request through an ISP to access servers where they can view web pages and download files. The servers provide these files through their ISP.

Examples of ISPs include AT&T, Comcast, Verizon, Cox, and NetZero. These ISPs may be wired directly to a home or business or beamed wirelessly using satellite or other technology.

What Does an ISP Do?

Most homes and businesses have a device that connects to the internet. It's through that device that phones, laptops, desktop computers, and other internet-capable devices reach the rest of the world — and it's done through an ISP.

Here's an example of the role an internet service provider plays when you download files and open web pages from the internet.

When you use your laptop at home to access a page on a site such as Lifewire.com, the web browser uses the DNS servers that are set up on the device to translate the Lifewire.com domain name to the IP address that it's associated with, which is the address that Lifewire.com is set up to use with its ISP.

The IP address is sent from your router to your ISP, which forwards the request to the ISP that Lifewire.com uses.

At this point, the ISP for Lifewire.com sends the page to your ISP, which forwards the data to your home router and to your laptop.

All this is done quickly — usually in seconds. However, for this to work, both the home network and the Lifewire.com network must a valid public IP address, which is assigned by an ISP.

The same concept applies when sending and downloading other files such as videos, images, and documents. Anything you download online is transferred through an ISP.

Is the ISP Experiencing Network Issues or Am I?

When you can't open a website, try a different one. If other websites display properly in the browser, your computer and your ISP aren't having issues. Either the web server that stores the website or the ISP that the website uses to deliver the website is having problems. The only thing you can do is wait for them to resolve it.

If none of the websites work, open one of those websites on a different computer or device in the same network. For example, if your desktop computer doesn't display the website, try it on a laptop or phone that's connected to the same Wi-Fi network as the desktop computer. If you can't replicate the problem on those devices, then the issue is with the desktop computer.

If the desktop computer is unable to load any of the websites, restart the computer. If that doesn't fix it, change the DNS server settings.

However, if none of the devices can open the website, restart the router or modem. This usually fixes network problems. If the problem persists, contact your ISP. It's possible the ISP is having problems, or it disconnected your internet access for another reason.

If the ISP for your home network is down, disconnect the Wi-Fi on your phone and use your cellphone data plan. This switches your phone from using one ISP to using another, which is one way to get internet access when your home ISP is down.

How to Hide Internet Traffic From an ISP

Because an internet service provider provides the path for all your internet traffic, it can monitor and log your internet activity. If this is a concern for you, one popular way to avoid tracking is to use a virtual private network (VPN). A VPN provides an encrypted tunnel from your device, through your ISP, to a different ISP. This hides your traffic from your ISP. Instead, the VPN service can see your traffic, but most VPNs don't usually monitor or log.

More Information on ISPs

An internet speed test shows the speed you get from your ISP. If this speed differs from what you pay for, contact your ISP and share the results.

Who is my ISP? is a website that displays the internet service provider you use.

Most ISPs give out always-changing, dynamic IP addresses to customers, but businesses that serve websites usually subscribe with a static IP address, which doesn't change.

Other types of ISPs include hosting ISPs, like ones that host email or online storage only, and free or nonprofit ISPs (sometimes called free-nets) that provide free internet access usually accompanied by advertisements.