When you’ve heard about Solid or the personal data web, you’ve probably heard about the idea of a pod and a virtual data vault.
But, contrary to what many people think, in a personal data web, a pod is not the same as a personal data vault.
To understand the difference, I’ll explain the basic workings of a personal data web.
As you know there are many different organisations that store data about you. Your supermarket, your bank, your government and so on and a personal data web allows you to bundle all this information in a single virtual data vault.
To do so, a personal data web distinguishes between three levels at which data is combined.
The lowest level is the data pod. Each of the organisations that have data about you, bundle this data in a personal data pod. This means that each organisation will have a pod especially for you and you will have a pod at each organisation.
Such a personal data pod contains both data about you like your name or your address, and data about this data such as why your name may be used for and the time your address last changed.
When organisations bundle your data in a pod, they do not necessarily have to disclose every piece of data. If they really want, they can still hide certain parts of your pod from you.
Next to hiding, organisations can also choose to grant you read or write access to certain parts of your pod. Whether or not you will be granted write access to your data depends on whether you own the data or not. For example, it is highly unlikely that your bank will grant you write access to the data about your checking account balance.
The middle level is the pod store. Organisations will have a pod store that contains all the pods they maintain for their employees, their customers or their citizens. This piece of software would probably run on a server at the organisation itself.
In addition, pod stores can also be provided by independent organisations. For example, you might, for example, pay GoDaddy, Amazon or NameCheap to provide a pod especially for you.
At the top level, you have a virtual vault that functions - more or less - like a browser.
This vault is virtual, because it does not really exist nor stores actual data. Instead, the vault is simply an application that gathers all information out of your pods and combines all that data into a single interface. Even if these pods are stored in the pod stores of several distinct organisations.
To connect your pods, you can simply go to a directory that contains a list of all known organisations with a pod store.
Thus, in conclusion, you, as a person will have a virtual vault that contains no actual data, but is connected to the many pods that organisations store for you.
It is exactly this architecture that makes the personal data web so unique: you can get an overview of all your data even when this data is stored at different organisations.