Project WP #654: WP6 - Supporting Blue Economy: VREs Development [Months: 1-30]
Project Task #656: T6.2 Strategic Investment analysis and Scientific Planning/Alerting VRE [Months: 1-30]
|Status:||Closed||Start date:||Jan 18, 2016|
|Priority:||Normal||Due date:||Dec 31, 2016|
|Assignee:||Nikolas Laskaris||% Done:|
In the context of the platform, a logical layer is simply a uniquely identifiable set of physical layer replicas. The operations upon logical layers are performed by a pair of components, namely the Logical Layer Broker and the Logical Layer Manager.
The Logical Layer Broker accepts a layer unique identifier and locates and returns the corresponding physical layer. Since there are in general more than one physical layer replicas, the broker will be able to perform load balancing according to a configurable policy.
The Logical Layer Manager is tasked with update operations upon logical layers, namely delete and insert. Its main task is to maintain the number of replicas at the configured levels and to keep inconsistencies to a minimum.
In order to access and manage the layer replicas, both components access a common logical layer catalog which retains the location of each replica and is updated when specific events occur in the cluster, e.g. a node went down, a new logical layer is created or a logical layer is deleted.