Askemos

The Askemos application space consists of nodes and edges. Nodes represent persistent applications (including users interaction) while edges identify communication channels to other nodes. By holding a named edge (a.k.a. link) a source node expresses interest in continued existence of the target.

The basic node-objects (termed places) of the Askemos DVM execute a process step when they receive a message. A reply function

reply = function(place, message)

is computed in each step, where

• reply: an aggregate denoting the answer the process step yields to the incoming message.

  A programmer who is used to hardware operating system terms might think of the reply element content as a list all those system calls which the function needs to complete and which might modify values.

• function: a single step response, a two-ari function; defined by the governing object type contract.

• message: A read only accessor to the aggregate denoting the current input.

• place: A r/o (read type request) or r/w (write type request) accessor to the aggregate denoting "this" place. Often called "me".

These process steps are executed by several physical machines in parallel and a byzantine agreement over the value of the reply is required for the step to be actually performed.