Dynamic DNS

DnsUp the first Dynamic DNS service with clear European connotations accessible worldwide.

DnsUp offers free and paid solutions and is aimed at all users who need to have their services always at hand.

The DNS (Domain Name Sytem) is a system that allows to pairs a name with an IP address. In fact, the machines work better with numbers and therefore to identify themselves they use the ip addresses (ex: 216.58.205.174) while the people remember better the names (es: google.com) .

When you type "google.com" or "www.google.com" on the browser's address bar, the Internet architecture is such that the appropriate DNS server is contacted and returns the associated IP address (216.58. 205.174 in this case). Through this address, the browser is able to unequivocally recognize the server that manages the Google word wide web service and retrieve the requested page, specifically the one related to the search engine.

When Internet was invented it was not thought that it would become so pervasive. Initially there were a few dozens of computers connected to each other and each of them was identified by the ip address (the same one we use today). With the current system it is possible to generate 4 billion different IP addresses, that is to say 4 billion devices connected to the Internet at the same time, a goal that was thought to be unattainable.

Over the years, the number of users has grown at an incredible rate and it was no longer possible to statically assign ip addresses to each connection. It was therefore thought to assign the ip addresses to the need, that is dynamically.

Every internet service provider (isp) has a limited number of ip addresses that assigns to the user randomly when it connects and that can change over time even if the connection remains.

In this way the user is able to access the internet without having a unique identity (IP address), but this is not a problem in most cases and often it is a behavior that is not perceived.

Once you understand what DNS is and how IP addresses are assigned it is easy to understand the role of Dynamic DNS.

The Dynamic DNS is a system that maintains the association between a name (eg: myhost.dnup.eu) and a machine (server or router) by updating the IP address on time, which changes in time.

Let's see a simple user story:

The NAS server (A) of the local network accesses internet (D) through the service provider (C).
The router (B) has two addresses: a private (B1), chosen by the LAN administrator, and a public (B2) assigned dynamically by (C).
The subject (E), owner of the LAN, wants to contact the server to retrieve a document, but to do so he must know the address (B2) which, being dynamic, changes with a certain frequency.
Fortunately (E) has a subscription to dnsUp which, thanks to the update client knows the public address B2 and keeps updated the association between the hostname myhost.dnup.eu and the router (B).
In this way (E), to access the NAS server (A) and all its services, it must simply remember the name "myhost.dnup.eu" that has been configured on dnsUp.

Dynamic DNS is used to have its services always at hand. The services that a local network can provide are multiple, for example:

• NAS server for centralized document management
• Cameras for the surveillance of the premises
• Private cloud server, for example Nextcloud
• Peer-to-peer services for sharing data
• DLNA server for the distribution of multimedia contents
• Customized services for corporate mobile devices

We could go much further with this list, but it is now clear that all the services of a local network can be usable outside through the right configuration of the router and the use of a Dynamic DNS.

The url is a text string that identifies a resource. For example:
http://www.dnsup.eu
The domain is the part that follows the type of protocol (http in this case) and is interpreted from right to left. We therefore have:

• the top-level domain, eu (Europe) and it must be chosen from a wide list, but in any case not modifiable (if not by the competent authorities)
• the second level domain, dnsup which can be freely composed
• the third-level domain, not necessary, but often used to identify the type of service offered (for example www means the world wide web, but it is only a convention)

Basically the domain includes the first and second level (dnsup.eu) and this is enough to create an association between name and ip address.

Dynamic DNS services allow you to freely choose the third level domain, while all the following can be selected from a list or chosen (depending on the type of subscription).
Among the possible domains dnsUp offers dd1.biz with which you can compose your own domain, so for example myhost.dd1.biz is a valid choice.

Let's see what the various plans offer:

• Free: this plan is offered free to test, without time limits, the quality of the service. In this case the available domain is dd0.eu
• Enhanced: in this case two domains are available, dd0.eu and dd1.biz
• Plus: this plan provides the same domains that we find in Enhanced and in addition you can indicate a domain of your choice for each subscription
• Managed: the managed plan provides the domain indicated by the user