What's DDNS

A good guide for DDNS and more

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So what’s DDNS?
DDNS is a technique that keeps on top of the IP address your ISP assigned to you. Periodically, and fairly often, a program runs to find out what your ISP provided internet IP address is at this moment. Then a private company somewhere on the internet is contacted and associates your current IP address with an internet name you provided to them. The internet name is a composite of a name you chose and their actual domain name. When someone on the internet enters that name in a browser, they’re talking to you.

For example, Asus offers a free DDNS service for buyers of some of the products they sell. I own an Asus router and use their DDNS service. Within the router, I turned the DDNS feature on and entered a name. Asus agreed the name was unique and established the link within a couple of seconds. The router relays my current IP address to Asus DNS servers several times a day. I now have an accessible internet presence at ________.asuscomm.com.

Behind the scene, the internet DNS service sees the ‘asuscomm.com’ part of the name and routes the search to the Asus DNS servers. Asus finishes the job and matches ________.asuscomm.com to whatever my ISP has decided my IP address should be at that moment. From this, the internet knows where to find me.