A very nice part of the Link framework is a concept called Configuration Keys. The idea with configuration keys is that you can define custom attributes for entities like partners, document types, message formats and distributions. You create configuration keys through the Link Administration Tool (explained in its own section).
If you want to define a configuration key, to specify an attribute for a partner, there are two ways of doing this. The first one is creating a general partner configuration key. This means that a value for that key can be specified for all partners. Or you can create a specific partner configuration key, where you specify a partner when creating the key in the Link Administration Tool. That configuration key will the only be usable for that specific partner.
When you have created you partner configuration key, it will be presented in the “Configuration keys” tab in the partner view of the user interface. Here value can be specified. The Link includes BizTalk mapping functoids which you can use to access the values of these keys.