Manage Your Account

 

Our DNS servers are changing

 

Time Warner Cable Business Class DNS servers are changing.


Because these settings are on your devices and not on the modem supplied by Time Warner Cable Business Class, we cannot make this change for you.


In some cases, customers that should be set up for DHCP have incorrectly set a static DNS server. This will eventually cause problems for the Internet connection, and these customers should contact their IT departments to assist with correcting these problems.

 

We realize that not all small companies will have an IT staff, and Time Warner Cable Business Class will attempt to assist in determining if this is the case and correcting the problem. In some cases, you may still need to hire a consultant if you are unable to do this yourself or with our assistance.

 

Explanation for some common devices

 

Configuration for some common Cable/DSL routers can be found on the manufacturers' websites as well as via the links we have provided below for some common configurations.

 

What is DNS anyway?

 

Before we get into DNS, we need to explain what an IP address is. Every PC and server has an IP address on the Internet. It has the format of four numbers, separated by periods, and looks like "1.1.1.1". Each number should be between 0 and 255.

 

Think of it as your phone number on the internet; it must be unique. It would be bad to have two different houses with the same phone number, and it would be bad to have two different machines (more properly known as “hosts”) that have the same IP address on the Internet.

 

For most people, it is much easier to remember http://www.timewarnercable.com than it is to remember "204.235.121.191".

How does your PC know where to find www.timewarnercable.com? Remember that each machine has an IP address? There is a way to translate from the easy-to-remember domain name to the hard-to-remember IP address.
Enter DNS. DNS is an acronym for "Domain Name Service". Its whole purpose in life is to translate between the friendly www.timewarnercable.com and the not-so-friendly 204.235.121.191. It handles this translation for web sites, email, FTP servers, database servers, or any machine within a domain name.

Let's dig into the process of how that works. Let's use the example that John Smith types www.timewarnercable.com into his web browser. How does his PC find the web server that has the page he's looking for, among the thousands of web servers?

  1. John types in www.timewarnercable.com to his browser.
  2. John’s PC looks at its configuration. It will find something called "DNS Server" or "name server" and there will be an IP address associated with that. Let's say it is 24.92.226.11. John's PC sends a message to 24.92.226.11 and asks, "I am looking for the IP address of www.timewarnercable.com, can you tell me what it is?"
  3. The DNS Server (24.92.226.11) gets the message and, assuming that the server already knows the IP address of www.timewarnercable.com, tells John's PC that the IP address is 204.235.121.191.
  4. John's PC gets the message that the IP address of www.timewarnercable.com is 204.235.121.191. So his PC sends a message to the DNS server and asks "send me the default web page at 204.235.121.191".
  5. The web server (whose IP address is 204.235.121.191) sends the web page to your browser. That is a simplistic example of how your PC finds a particular web-server and web page. The process of matching a domain name to an IP address is called resolving. So your PC resolves the IP address from the domain name. Let's get into a little more detail.

In step 1, how does John's PC know that the IP address of the DNS Server is? There are two ways it learns what the address is. The first is that John asked his ISP what the address was and entered it himself. There are times manually entering (also known as statically entering) the address is necessary or desirable, but usually the ISP automatically tells your PC what the IP address of the DNS server is.

This process is called "DHCP" or Dynamic Host Configuration Protocol. When you select "Obtain IP address automatically" in your Windows Network Connections page, you are telling your PC to use DHCP and to ask the ISP to give you the DNS Server address (amongst a bunch of other things).

The second way to obtain the IP address of the DNS server is to use static IP addresses.   This is more common for a business connection; however, most small businesses will just use DHCP. The IP address and the DNS server information is entered locally on a computer or router that runs DHCP for computers in the office.

To summarize the previous paragraphs; John's DNS server receives a request from a PC on the internal network for an IP address that it doesn't know. John's DNS server then makes a request to a top-level domain server and gets a response where to go to get the information that John's DNS server is requesting. John's DNS server then makes a request of the authoritative server and forwards the answer it receives to the PC on the internal network that made the original request.
It sounds long and complex, but it happens very quickly. One way to speed up the process is called caching. Caching is when the DNS server remembers the original response from the authoritative server for a period of time. So if Claude makes the same request five minutes after John did, the DNS server doesn't have to repeat the whole process.
So now you might be asking, “How do I make this change, and why can’t Time Warner Cable (TWC) make the change for me?” In most cases, TWC cannot make the change for the customer because it is set on a device that the customer owns. If the customer has TWC's Managed Security product, TWC can make changes for the customer. Usually this involves TWC setting up a Sonic Wall firewall at the customer's location then doing remote management of the firewall. This entails a monthly charge to TWC, so some businesses will opt to have an independent computer consultant come in and for a one-time fee set up a router, computer, or a firewall for them.  If an adjustment is needed in the future, the customer would call the consultant and have the consultant make any needed changes.  This would most likely involve another one-time charge by the consultant.

 

The TWC commercial DNS servers are 24.92.226.11 and 24.92.226.12. If you are a commercial customer using static IP addresses, you should be using these two DNS server addresses.

 

Configuring a Windows PC as a DHCP client

Use these steps to configure a Windows PC as a DHCP client:

  1. Open the Windows Control Panel and then double-click the Network Connections icon to open a list of network connections.
  2. Double-click your current connection to the network.
  3. In the resulting Status dialog box, click Properties.
  4. In the Local Area Connection Properties dialog box, select Internet Protocol (TCP/IP) and then click the Properties button.
  5. In the Internet Protocol (TCP/IP) Properties dialog box, select the “Obtain an IP Address Automatically” option.
  6. Select the “Obtain DNS server address automatically” option.
  7. Click OK and close all open dialog boxes.

When you set your computer to obtain an IP address automatically, it will get the address from a DHCP server.
Configuring a Mac as a DHCP client

Follow these steps to configure a Mac as a DHCP client:

  1. Open System Preferences from the Apple menu and click the Network icon.
  2. In the resulting Network control panel, click the Show menu drop-down arrow and choose the network connection you use to connect to the network If your computer connects to the network using the built-in Ethernet network port, choose Built-In Ethernet in the Show menu. If you connect using an AirPort Card, choose AirPort in the Show menu instead.
  3. Click the TCP/IP tab.
  4. Click the Configure menu drop-down arrow and choose Using DHCP.
  5. Click the Apply Now button and then close the Network control panel.
  6. Press Command Q to quit System Preferences and then restart your computer.