“Hey Jarid, did you see that video I sent on 172.217.8.174?” “Yeah Chris, Sara posted it on 157.240.26.35 but I only found it because I 172.217.4.78’ed it”.
Sound cryptic? Thank DNS for helping humans decode the internet domain name addresses we use to the number system our computers use.
Every computer on the internet has an address called an IP Address. Information is sent and received by IP addresses, not by domain names. The DNS system is the process that converts the domain name you type into your browser into the IP address of the system you are trying to reach.
When you type ‘facebook.com’ into your browser, the query is first sent to a DNS server who takes the domain name and converts it into the IP address of the computer you are trying to reach. This IP address is returned to you and then the real request is sent out. Anytime you use a domain name online, it must be converted to an IP address by a DNS Server.
In reality, IP Addresses for popular domain names usually represent a load balancer of some sort which will send the query to one of many systems ready to handle your request.
DNS Servers talk to each other to make sure they have the latest information. If you request the address for google.com and the DNS Server does not have it, it will know where to look. The next person that requests google.com from the DNS Server will likely get the cached answer. The same thing happens locally on your computer. DNS query results are cached and re-used until a self-imposed time limit has been reached and it will ask the DNS server for a fresh IP.
Most DNS queries are handled by your Internet Service Provider’s DNS Servers. The DNS Server is assigned to your computer at the same time your internet address is assigned so the computer knows where to send the requests. Depending on Internet Service Provider, this DNS query can take a little time which can add up quickly. 3rd party DNS servers exist that can be used instead of the one provided by your ISP and this can lead to faster speeds under certain circumstances.
Christopher Carlson, MA, MBA is a Grand Rapids native. He leads the critical database team for Optum, a part of UnitedHealth Group. He has an undergraduate degree from Minnesota State University, Mankato as well as graduate degrees from St. John’s University and St. Mary’s University of Minnesota. He resides in Grand Rapids with his beautiful wife and wonderful daughter.
Gloss