Warrant

A right to use a service, represented as XML.

Another way to think of a warrant is that it is evidence of a contract. If a contract has been arranged (on- or off-line) then a warrant will result so that the service can be used and the contract fulfilled.

When a client netlet wants to use a service it presents its warrant to the node which then finds and binds the server netlet. Of course, for a node to use a warrant to find the right netlet the warrant needs to contain either a descriptor or a URL reference of where to find that descriptor--Figure . So to make use of a service, a netlet needs only a warrant. This contains everything a node needs to find and bind a service, however indirectly.

Figure: A warrant is a right to use a service. Among other things it must contain a descriptor for the relevant netlet, or a reference to one.

Figure: Warrants A and B are both for use of a file storage service. But warrant A limits its holder(s) to a specific group of files, while warrant B is limited to a different group. Thus each warrant-holder has access only to their files.

A warrant is not just a general right to use a service--it is very likely to be limited for the terms of the particular contract for which it was issued. Two netlets may have warrants to use a service, but one may be time-limited, and another may be resource limited. That's up to whoever arranged the contract. In Figure  different warrants for the same service allow their holders access only to their area of that service.

The contents of a warrant is signed to prevent tampering.