Descriptors and security

To run a netlet a node needs a descriptor. This is a bundle of information that allows a node to load and run the netlet. It contains program code or locations of where to find this code, or both.

A descriptor can also contain both digital signatures (to help the node know whether to trust it) and initialisation information.

This helps a netlet reproduce: it can send a descriptor of itself to a new node together with enough information to help it pick up where it left off. The node creates the netlet based on the descriptor and starts it in exactly the right way.

Netlet reproduction is illustrated in Figure . This is how nodes can offer hosting services, and we discuss this later.

Figure: Netlet reproduction. Step 1: A netlet its descriptor to the new node, via a second netlet which facilitates the hosting service. Step 2: The new node uses the descriptor to create the netlet and initialise it in the right way. Thus a new copy of the netlet is running in a new location.