A Dynamic Domain Name System or DynDNS is a method of automatically updating a name server in the Domain Name System (DNS), often in real time, with its configure hostnames, addresses and other information.
The term describes 2 different concepts:
- Dynamic updating refers to systems that are used to update traditional DNS records without manual editing by using TSIG mechanism to provide security as explained in the RFC 2136.
- DynDNS permits lightweight and immediate updates which do not use the RFC 2136 standard.
A Domain Name System  or DNS is a global database that translates domain names (i.e. www.google.com) to internet addresses that are used by computers to talk to each other.
DNS also provides other information about domain names such as mail services.
Why should you use a Dynamic DNS?
- Remote Access your computer, DVR, webcam, security camera or any Internet connected device easily.
- Dynamic DNS points an easy to remember hostname to your dynamic IP address.
Case: Watching the USA version of Netflix in Germany using Apple TV.
When you try to watch NetFlix in Germany you will get the German NetFlix with the options for language and subtitles of Germany.
That's not what you want.
- Because the German version is with all series later than the USA.
- Because you want the original language (that's not the problem) and subtitles in your language (that's the pain in the ass).
To do this, you will need a VPN. See Virtual Private Network (VPN). Please note that not all VPN providers are capable to view NetFlix.
With a VPN you are capable to view NetFlix on an iPod, and iPhone and in a Browser.
But not on an Apple TV.
Ok, than I am going to use AirPlay to stream from my iPhone/iPad to my TV.
Helas, that is not going to work.
Why? NetFlix do not allow you to use an external Screen and also AirPlay is blocked.
Can I use Apple TV to view the USA version in Germany?
Yes. You still need the VPN, but also a DynDNS to get a simple IP-Address which is connected to your (non) static ISP.
You'll have to ask you VPN provider how to do this. ExpressVPN has tutorials for this purpose. See ExpressVPN, Stream to Apple TV older generations with DNS.
In the end you still need to install ExpressVPN on your router.
It is possible, but you'll have to do nasty things. My advice: If you do not have trouble to do it, do it, elsewhere just don't.
- Internet Society, The definition is taken from their website..