How can I improve my internet performance with DNS information in my router?

There are dozens of tips on the web from MTU size to tweaking network card or wireless router alternate firmware.  What isn’t covered a lot is DNS queries.   DNS or Domain Name Services is used when you type the ‘friendly’ name (url) into your address bar of your browser.   The friendly name goes out onto the worldwide web to your ISPs DNS servers where it is changed to an IP address and routing then takes place.

How can you improve this?  Here’s some ideas.  When programming your router, you can statically define the DNS servers in your router and disable DNS Relay.  This will cause the dhcp leases to contain the hard coded ip addresses of the DNS servers you typed in instead of the router’s  ip address (leaving DNS relay on, your router will act as the go between).   With several combinations, which is best?

If your router has a SPI firewall, the impact of this is that the stateful-packet-inspection (SPI) table will have to track additional DNS(Port:53)  streams as each individual  device (tablet, computer, smartphone, smart TV) makes its unique request (websites typed into the address bar) directly to the DNS servers on the Internet.

You can program your router with several options.  Here are a few combinations.

DNS Relay on Your router DNS Servers entered into the
Pros Cons
Enabled Yes Computers receive fixed local DNS server number. Your router can immediately proxy dns queries and you can travel directly to your site.  Use your router’s IP as the first DNS address and a public DNS as the secondary.  Fastest DNS servers (secondary) could change (rare) and become out of date
Enabled No Computers receive fixed local DNS server. Router receives update-to-date DNS entries. Some small delay in  querying a website
Disabled Yes Computers receive fixed DNS servers. DNS queries are now part of your standard traffic and are inspected by the SPI engine. Can be slower.
Disabled No Computers receive your ISP’s update-to-date dns server entries if known. Request pass through to outside DNS servers and can be slower

If you need to check your DNS entries after you save your router’s settings, in Windows, go to a command prompt and type ipconfig /all. Running Linux? Type ifconfig to get your IP address or cat /etc/resolv.conf  to get your ip address and dns  information after you program and reboot your router.


About TCAT Shelbyville IT Department

The Tennessee College of Applied Technology - is one of 46 institutions in the Tennessee Board of Regents System, the seventh largest system of higher education in the nation. This system comprises six universities, fourteen community colleges, and twenty-six Applied Technology Colleges.
This entry was posted in Apple, Computer hardware, Computers, Home Networking, Internet, Linux, network, Networking, Windows and tagged , , , . Bookmark the permalink.

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