Knowledge Base

What is DNS and Why Should It Be Changed?

DNS (Domain Name System) is like the internet's phone book. It allows us to use easily memorable domain names (e.g., google.com) instead of IP addresses that are difficult for people to remember. When you type a domain name into your browser, DNS servers translate that domain name into the corresponding IP address, allowing your browser to connect to the correct server.

Reasons to Change DNS:

• Faster Internet: Different DNS servers operate at different speeds. You can increase your internet speed by using a faster DNS server.
• More Secure Internet: Some DNS servers protect you and your devices by blocking access to malicious websites.
• Bypassing Censorship: In some countries or networks, access to certain websites may be blocked. You can bypass this blocking by using a different DNS server.
• Reliability: If you are experiencing problems with your default DNS server, you can maintain your internet connection by using a different DNS server.
• Customization: Some DNS servers offer additional features such as ad blocking or parental controls.

Important Note: Changing DNS can sometimes cause problems with your internet connection. Therefore, it is important to note your current DNS settings before making changes and to be able to revert to the old settings if you experience problems.

How to Change DNS in Windows? (Step by Step)

You can follow the steps below to change DNS in Windows:

1. Open Control Panel: Type "Control Panel" in the Start menu and open it.
2. Click on Network and Internet: In the Control Panel, click on "Network and Internet".
3. Click on Network and Sharing Center: In the "Network and Internet" section, click on "Network and Sharing Center".
4. Change Adapter Settings: Click on "Change adapter settings" from the menu on the left.
5. Select Your Network Connection: Find your existing network connection (Ethernet or Wi-Fi), right-click on it, and then select "Properties".
6. Select Internet Protocol Version 4 (TCP/IPv4): In the window that opens, find "Internet Protocol Version 4 (TCP/IPv4)" and double-click it or select it and click "Properties".
7. Specify DNS Server Addresses: Check the "Use the following DNS server addresses" option and enter the addresses of your preferred DNS servers.
8. Save Changes: Click the "OK" button to close all windows.

Example DNS Server Addresses:

Changing DNS via Command Line:

You can also change the DNS in Windows via the command line (cmd). This method is especially useful for quickly changing DNS settings on multiple computers.

1. Run Command Prompt as Administrator: Type "cmd" in the Start menu, right-click on "Command Prompt" and select "Run as administrator".
2. Find the Network Interface Name: List the names of your network interfaces using the following command:

netsh interface show interface

1. Change DNS Settings: Set the DNS server addresses using the following commands. Replace "NetworkInterfaceName" with the name of your network interface and replace "PrimaryDNS" and "SecondaryDNS" with the addresses of your preferred DNS servers.

netsh interface ipv4 set dnsname="NetworkInterfaceName" source="static" address="PrimaryDNS" validate="no"
netsh interface ipv4 add dnsname="NetworkInterfaceName" address="SecondaryDNS" index=2 validate="no"

1. Verify Changes: You can use the following command to verify that the DNS settings have changed:

ipconfig /all

Example Command Usage: Suppose the name of the Wi-Fi interface is "Wi-Fi" and you want to use Google Public DNS. The commands would be as follows:

netsh interface ipv4 set dnsname="Wi-Fi" source="static" address="8.8.8.8" validate="no"
netsh interface ipv4 add dnsname="Wi-Fi" address="8.8.4.4" index=2 validate="no"

What to Do After Changing DNS

After changing the DNS settings, you may need to take some steps for the changes to take effect:

• Clear the DNS Cache: Windows stores DNS records of websites you have visited before in its cache. You may need to clear this cache for DNS changes to take effect immediately. Open the command prompt as administrator and run the following command:

ipconfig /flushdns

• Clear Browser Cache: Your browser may also store DNS records in its cache. Clearing your browser's cache can help ensure that DNS changes take effect. You can clear the cache by going to your browser's settings.
• Restart Your Computer: In some cases, you may need to restart your computer for DNS changes to take effect.

DNS Selection: Which DNS Server is Better?

There are several factors to consider when deciding which DNS server is better for you:

• Speed: Different DNS servers operate at different speeds. You can compare the speeds of different DNS servers using speed test tools.
• Reliability: A reliable DNS server operates continuously and provides a smooth internet experience.
• Security: Some DNS servers protect you and your devices by blocking access to malicious websites.
• Privacy: Some DNS servers encrypt your DNS queries and do not track them.
• Additional Features: Some DNS servers offer additional features such as ad blocking or parental controls.

DNS Server Comparison:

Real-Life Example: A user notices that their internet speed has slowed down. After doing some research, they learn that there are problems with the DNS servers of their internet service provider (ISP). By switching to a faster and more reliable DNS server such as Google Public DNS or Cloudflare DNS, they significantly increase their internet speed.

Problems and Solutions That May Be Encountered During DNS Change

While the DNS changing process is usually smooth, you may encounter problems in some cases. Here are the most common problems and solutions:

• Internet Connection Interruption: If you have entered incorrect DNS server addresses or the DNS server is not working, your internet connection may be interrupted. In this case, revert to the old DNS settings or try a different DNS server.
• Inability to Access Websites: If you cannot access some websites, you may suspect that your DNS server is blocking these websites. Try a different DNS server to see if the problem is resolved.
• Slow Internet Speed: If you have selected an incorrect DNS server, your internet speed may slow down. Compare the speeds of different DNS servers using speed test tools and choose the fastest one.
• DNS Server Not Responding Error: This error means that the DNS server cannot be accessed. Check your internet connection, make sure the DNS server is running, and make sure your firewall is not blocking DNS traffic.

Case Study: A company's employees are experiencing problems accessing certain websites. The IT department discovers that the DNS server used on the company network is accidentally blocking these websites. They resolve the issue by correcting the DNS server's settings or using a different DNS server.

DNS and Security: What is DNSSEC?

DNSSEC (DNS Security Extensions) is a set of protocols designed to increase the security of the DNS system. DNSSEC ensures the authenticity and integrity of DNS queries and responses. This prevents attackers from modifying DNS records and redirecting users to malicious websites.

How Does DNSSEC Work?

1. Digital Signature: DNSSEC uses cryptographic keys to digitally sign DNS records.
2. Chain of Trust: The signature verification process starts with a root trust point and continues in a chain throughout the DNS hierarchy.
3. Data Integrity: DNSSEC guarantees that DNS data has not been modified or corrupted.

Why Should You Use DNSSEC?

• Prevent Phishing Attacks: DNSSEC prevents phishing attacks by ensuring that users are directed to the correct websites.
• Ensure Data Integrity: DNSSEC guarantees that DNS data has not been modified or corrupted.
• Prevent DNS Spoofing: DNSSEC prevents attackers from modifying DNS records and redirecting users to malicious servers.

Important Note: Enabling DNSSEC must be supported by the DNS server and domain name registration operator. Check if your domain name supports DNSSEC and follow the necessary steps to enable it.

DNS and VPN: How Do They Work Together?

VPN (Virtual Private Network) enhances your online privacy and security by encrypting your internet traffic and masking your IP address. When DNS and VPN are used together, your internet experience becomes more secure and private.

Relationship Between VPN and DNS:

1. VPN Tunnel: VPN creates an encrypted tunnel for your internet traffic. All your data passes through the VPN server.
2. DNS Queries: When using a VPN, your DNS queries are usually made through the VPN server. This prevents your ISP or other third parties from seeing which websites you visit.
3. DNS Leak: In some cases, your DNS queries may leak outside the VPN tunnel. This allows your ISP to see which websites you are visiting. To prevent DNS leaks, you should enable DNS leak protection in your VPN application.

DNS Settings When Using VPN:

• VPN Provider's DNS Servers: Most VPN providers use their own DNS servers. This ensures that your DNS queries are made through the VPN tunnel and that your privacy is protected.
• Private DNS Servers: If you wish, you can also use private DNS servers while using a VPN. However, in this case, it is important to consider the risk of DNS leaks and enable DNS leak protection in your VPN application.

Example Scenario: A user connects to a public Wi-Fi network. They encrypt their internet traffic and mask their IP address using a VPN. In addition, they prevent DNS queries from leaking outside the VPN tunnel by enabling the DNS leak protection of the VPN application. In this way, they browse the internet securely and privately on a public Wi-Fi network.

DNS Change and Game Performance

Low ping time and stable connection are critical for the gaming experience while playing games. DNS server selection can affect game performance. A faster and more reliable DNS server can allow you to connect to game servers faster and reduce your ping time.

DNS Selection for Gaming:

• Low Ping Time: Choose a DNS server that is close to the game servers and has a low ping time.
• Reliability: A reliable DNS server prevents disconnections and delays.
• Game Optimization: Some DNS servers are optimized for game traffic and offer better performance.

DNS Speed Test:

You can test the speeds of different DNS servers using various tools. These tests can help you determine which DNS server offers better performance for you.

Example: A player is experiencing high ping times and lag in online games. By testing different DNS servers, they find a DNS server that is closer and faster to the game servers. This reduces their ping time and improves their game performance.