Introduction¶
Many datasets at GEOFON contain restricted data. By this, we mean that access is limited to those people authorised by the data provider, typically, the PI(s). Who the PI authorises is their choice; we can help you request access if desired. Sometime an entire seismic network is restricted; other times only a few stations or channels may be restricted.
To ensure that we do not serve restricted data to unauthorised people, we must ask you to authenticate to our service - that is, present some credentials which identify who you are. You may use our services unauthenticated, but then we can only provide you with open (unrestricted) data.
We use a token-based system. The token is a cookie-like piece of data, containing identifying information, such as your name.
The token is for your personal use, and only one is needed for all the different data sets at GEOFON that you may be entitled to access.
The token is digitally signed by a trusted party 1, and has a fixed validity period.
You present the token to the service’s /auth method, at a URL such as https://geofon.gfz-potsdam.de/fdsnws/dataselect/1/auth
If the digital signature is valid, a temporary account for /queryauth is created.
You then use the /queryauth method to request data, instead of the usual /query method.
When a token expires, you simply go back to the trusted party to generate a new one.
Historically, our Arclink service asked for your user name (typically, your e-mail address), and served data which was encrypted using a password which had been sent to you previously. This approach is not possible using FDSN web services (fdsnws-dataselect, etc).
FDSNWS authentication is also supported by the latest version of WebDC 3.
On the next pages we show you:
How to obtain credentials (via a token).
How to use these to request data.
For advanced users, we provide some additional details in Authentication concept. Information about the personal data we retain is also there.
Note
We expect that there may be problems, misunderstandings, and gaps in the documentation. In case of difficulties, don’t hesitate to contact us. The Frequently Asked Questions section may help you.
- 1
What is a trusted party? Today, tokens are provided by the EIDA Authentication Service (EAS) at https://geofon.gfz-potsdam.de/eas . In the background we use a service which could act as a proxy to eduGAIN, in the case that your home institution allows it, or lets you create a local account. An eduGAIN Identity Provider serves as the trusted party - you give it, not us, your credentials, and it provides a token which we accept as proof of your identity. Both we and you trust the eduGAIN infrastructure to do this correctly.
