| What is DDNS? | | | | can communicate with the server either through |
| If we wish to run a server for website hosting or | | | | domain name (using DNS translation) or directly |
| accessing CCTV cameras, available from any | | | | via numeric address (bypassing DNS server). |
| Internet location - and we don't have a static IP | | | | What is a DDNS? |
| address but a dynamic one supplied by DHCP | | | | If we wish to run a server for website hosting or |
| server (e.g. ADSL service) - we have to use | | | | accessing CCTV camera, available from any |
| DDNS (Dynamic Domain Name System). DDNS | | | | Internet location and we don't have a static IP |
| server provides a database containing relations | | | | address but a dynamic one supplied by DHCP |
| between domain names and numeric addresses, | | | | server (Neostrada - ADSL service in Poland is a |
| which may be updated on request, by the domain | | | | good example of such an option), we have to use |
| owner. Thanks to this feature, the server is | | | | DDNS (Dynamic Domain Name System) service. |
| available in the domain name regardless its current | | | | How does DDNS work? |
| IP address. We have to remember that when | | | | Neostrada clients do not have a static IP - it is |
| DHCP server changes the IP, it takes some time | | | | changed periodically. As we have shown above, in |
| to detect this change by the client software or | | | | this situation it is impossible to run a server, |
| router. Then, after the notification has been sent | | | | because the current IP address of the server |
| to DDNS server, it takes another minute or so to | | | | would have been unknown. DNS server, which |
| send this piece of data to DNS server to update | | | | translates domain name into numeric form, points |
| the database. As a result, our server will be | | | | at one specific IP. Once the IP number changes, |
| periodically unavailable up to several minutes - | | | | the DNS data ceases to be valid. The solution is |
| every time the IP address has been changed. To | | | | provided by DDNS service. Similarly to DNS |
| use the service one has register at a DDNS | | | | server, it provides a database containing relations |
| server, e.g.: | | | | between domain and numeric addresses, but this |
| - DynDNS - | | | | database may be updated on request by the |
| - No-IP - | | | | domain owner. Thanks to this feature, the server |
| It is also needed to have a router capable of | | | | is available in the domain address regardless its |
| sending current IP address to the DDNS server. | | | | actual IP number. In such a case, the access to |
| From the TP-Link offer there may be used | | | | the server is limited to its domain name translated |
| access points with integrated routers and ADSL | | | | by DDNS server, unless we know its actual IP |
| modems, like TP-Link TD-W8910G and | | | | number (but of course we do not know how long |
| TD-W8920G, or routers with ADSL modems - | | | | it will be valid). We have to remember that when |
| TP-Link TD-8840 or TD-8841. | | | | DHCP server changes the IP, it takes some time |
| DNS (Domain Name System)is a service | | | | to detect this change by the client software or |
| translating an IP address from numeric to domain | | | | router, and, after the notification is sent to DDNS |
| name. It means that there is no need to | | | | server, it takes another minute or so to send this |
| memorize addresses in numeric form such as | | | | piece of data to DNS server to update the |
| 62.121.128.13 - you can always use adequate | | | | database. In result, our server will be periodically |
| name, for example DNS server will translate the | | | | unavailable up to several minutes, every time the |
| numeric address into domain name on request. | | | | IP address has been changed. |
| After the computer which made the request | | | | DDNS service is accessible via a number of |
| receives the numeric address, it can establish | | | | providers. Its basic version, sufficient to support |
| connection with the appropriate computer. | | | | the above configuration, is usually free of charge. |
| Such communication is possible if the server has a | | | | All devices supporting DDNS usually have several |
| static IP, at which it is always available. A single | | | | provider addresses preset by default. |
| record in DNS server database establishes relation | | | | DDNS configuration |
| between the addresses 62.121.128.13 and This | | | | All informations including images can be found on |
| relation is always valid and invariable, so the client | | | | Dipol web site. |