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> documentation > technical > protocol > v1.0

Protocol V1.0

Note that this protocol is obsolete, and should NOT be used anymore for developing new clients.
It has been added for backward-compatibility only.


Posting your IP address to the dyns server is done by opening a http connection (socket connection on port 80) to the web server and invoking a script similar to a CGI script.

Definition of terms

We'll explain the protocol with folowing imaginary data:
username: joe
password: foo
hostname: worldofjoe
Furthermore , we will assume that joe's current IP address is

Sending the request

The URL you have to request has this form:

If requested this way , the script will determine your current IP address for you. In some cases , this might not be what you expec ted. For example if your connection passes trough a proxy-server, the script will see the IP address of your proxy server instead of you r own IP address.
That's why we introduced an optional paramater to our script as you can see below:

So you can explicitly specify your IP address.(Note that all the parameters you specify will be sanity-checked before being process ed, so sending corrupted data to the script will result in a rejected update request)

Reading the result

The server returns a string which you can interpret in the following way:
To determine the result of the script, it's always enough to read the first 3 characters of the result string which represent a deci mal value. Following this value, a short description will be provided.
These are the different possible responses:

  • 400 Bad request
    Meaning: The URL was malformed, one of the required parameters was not supplied or the IP address you supplied in your request is i nvalid.

  • 405 Hostname 'worldofjoe' is not one of your hosts
    Meaning: The hostname you want to update is either nonexisting, or you are not owner of this hostname

  • 200 Host worldofjoe updated (
    Meaning: update was successful. For verification , the assigned IP address is shown in the result string.

Final remarks

The timeout value of nameserver entries in the domain has been set to 5 minutes.
If you perform a name-lookup of your host, the IP address of wolrdofjoe will be cached for 5 minutes by your nameserver (or y our ISP's nameserver) Keep this in mind when developing programs to post IP addresses.

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