You may not be aware of it but you can use free public DNS on your DLink DIR-300 wireless router. It's very simple to do this and you only have to enter one set of Internet Protocol (IP) address on the Internet setup page of your DLink DIR-300 wireless router. To remove the settings, you just have to delete those two IP addresses and save your settings.
Symptoms of the Problem
If your problem is slow speed, meaning there are just too many users for your limited bandwidth, this approach will not have any appreciable effect on your surfing. The solution in such a case is to rewire your connection to a larger bandwidth.
This workaround will only work if you're experiencing long times during DNS look-ups, that is, when you notice that your browser is getting stuck on the status of looking for the web page that you want to display on your browser. Your browser will provide you with messages on what is happening while you're surfing so try to read those messages. If you frequently experience getting stuck with such an error message in your browser, then this solution could be of help. Another error that you may observe is the timeout error when your browser basically gives up looking for the web page that you want displayed on your browser.
Every time that a web page is needed to be fetched from its server, a DNS look-up is performed. If your Internet service provided has too many clients that are simultaneously online, the DNS server in your network can be overwhelmed by too much demand. Thus, some requests might be dropped and if your service is on the lower bandwidth option, your packets will be the most frequently hit by this dropping action.
Your browser needs to know the IP address if the server where the web page that you're interested in is stored. Your DNS server is responsible for getting this information from the Internet. By default, your DLink DIR-300 wireless is setup to automatically get these information from your Internet service provider. However, you can choose to override this setting by changing the configuration or your wireless router.
Solution to the Problem
There are two ways by which this problem could be solved. You can either change the DNS server settings on your computer or the DNS settings on your wireless router. If you want, you can try first changing the DNS settings of your laptop's wireless adapter and see if there is any appreciable change in your surfing speed. You can use the Google DNS service by using the IP address 188.8.131.52 as your primary server and 184.108.40.206 as your secondary server. In your Vista laptop, look for the Manage network connection in the Network and Sharing Center of the Control Panel. Go to the Properties page of your wireless network adapter and change its Internet Protocol Version 4 settings. Instead of letting your computer use the automatic DNS settings, change the DNS IP addresses manually to the address I have given earlier. Don't forget to save your settings.
Google and OpenDNS are two of the free public DNS that are offered to be used in the Internet. Experts have generally observed some DNS performance problems on some networks particularly those at the end where Internet service providers operate. Free public DNS service is offered to alleviate this problem. This has the effect of decreasing substantially the work of the DNS server of small Internet service providers. It's one way of improving the traffic situation in the Internet.
If you find that it is working well on your laptop and there is significant change in your browsing speed, then it's time to adopt the solution to your home network. First, remove the manual DNS settings that you have made on your laptop if you have tried to test first how free public DNS works. You would be using the OpenDNS service on your wireless router so there would be no need to use another different free public DNS on your computer.
Type the local IP address of your DLink DIR-300 wireless router on the address bar of your Internet browser and enter your user name and password. On the middle portion of the page at the lower part, click on the Manual Internet Connection Setup button. Look at this page carefully and notice the two blank spaces in the middle bottom portion of the page. Type 220.127.116.11 on the space opposite Primary DNS address. Type 18.104.22.168 on the blank space opposite Secondary DNS Address. Click on the Save Settings button and wait for the page to come back again. Click on Status at top right-hand portion of the router configuration page. Click on the DHCP Renew button near the center of the window. Wait for the correct IP address numbers to show up. Click on the Logout button on the upper left hand side of the configuration page.
Go to your laptop and check if there has been a significant change on the speed of your browsing. Type a web address that you know of and that you have not used recently. Try to access the Internet on your smart phone or other gadget connected to your DLink DIR-300 wireless router. If you find that your browsing speed is still the same, your problem could be insufficient bandwidth, that is, your connection is too limited to satisfy the demands of the users on your network. Repeat the setup process that you have performed on your wireless router and erase the IP addresses on the primary and secondary DNS portions of the configuration page. Save your settings and log out of the settings page. However, if you found that your surfing speed has improved, then you don't have to do anything. Just leave the settings unchanged.
Maintain the new settings for a few days. If you experience delays in your DNS look-ups (long looking up message and can't find server message), OpenDNS may be experiencing congestion problems. Use the Google primary and secondary DNS addresses instead.
Read my other article on Internet Protocol addressing for setting up DHCP on your DLink DIR-300 wireless router at; http://publishtoweb.blogspot.com/2011/12/internet-protocol-addressing-for.html.
Read my other article on how you can access your DLink DIR-300 wireless router from the Internet at: http://publishtoweb.blogspot.com/2010/01/how-you-can-access-your-dlink-dir-300.html.
Read an article on how to use Google DNS service to speed up Internet on your Vista laptop at: http://sites.google.com/site/ournewapproach/use-the-google-dns-service-to-speed-up-internet-on-your-vista-laptop.