Create a network

Alchemist nodes can connect to each other and form a network.

The network-model key is used to load the implementation of LinkingRule to be used in the simulation, which determines the neighborhood of every node.

The key is optional, but defaults to NoLinks, so, if unspecified, nodes in the environment don’t get connected.

Omitting the key is equivalent to writing any of the following:

network-model:
  type: NoLinks

network-model:
  type: NoLinks
  parameters: []

Linking nodes based on their respective distance

One of the most common ways of linking nodes is to connect those which are close enough to each other. To do so, you can use ConnectWithinDistance, passing a parameter representing the maximum connection distance.

Note that such distance depends on the environment: while the definition of distance is straightforward for euclidean spaces, it’s not so for Riemannian manifolds, which is a fancy name to define manifolds such as the one typical of a urban map (you can roughly interpret it as a euclidean space “with holes”).

For instance, in case of environments using GeoPosition, the distance is computed in meters, so the distance between [44.133254, 12.237770] and [44.146680, 12.258627] is about 2240 (meters).

In the following example, nodes are connected when closer than a threshold:

incarnation: sapere # The incarnation is always mandatory
network-model:
  type: ConnectWithinDistance # Loads a class with this name implementing LinkingRule
  parameters: [2] # Connection radius (parameter of a ConnectWithinDistance's constructor)
deployments:
  - type: Point # Loads a class with this name implementing Deployment
    parameters: [0, 0] # Coordinates
  - { type: Point, parameters: [0.5, 0.85] }
  - { type: Point, parameters: [-0.5, 0.85] }