Federation is one of the key elements of sense and ensures the overall system automatically establishes real-time relationships between all the discoverable sense nodes in a network, irrespective of the physical location or runtime infrastructure of the nodes themselves.

A sense node is a computational instance that is able to provide and manage all sense services, and to make them join virtually with others of the same service family installed on other parts of the network. This means that all services from the same family are visible to each other no matter where they are installed. Belonging to the same service family means being able to provide the same set of services to a requester, but perhaps using a different implementation or indeed perhaps a completely different service provider.

When joining a federation sense will monitor the status of the federation and the status of all the services within the federation by:

• monitoring each node’s perspective from all other nodes – which means no centralized controller or single-point-of-failure
• acquiring information regarding all the available protocols that the services on the nodes have made available – allowing sense to instruct intra-sense communication multiplexing on the most efficient protocol available at the time the communication is needed, again increasing system resilience

A federation snapshot is available through the sense web console and shows which nodes and services are running in the network and how they are performing. The federation is the unique place where information about services, feelings, business flows and nodes is stored together with their individual and collective ‘health’ status.

The sense federation enables services to compute on the same virtual space of computing resources and to be extended from one space to another.

sense federation

(more…)

sense is continually balancing the load on the system system by dynamically allocating all the available ‘healthy’ resources to satisfy the incoming requests. However, there are situations where resources are just not available and/or have been withdrawn from service (planned or unplanned), yet the system as a whole must continue to be reliable.

Every resource inside sense including services, feelings and business flows can associate a mock strategy in the case of the worst SLA situation i.e. a defined response even if the service, feeling or business flow being called is completely down

A mock strategy is used in a situation where sense does not invoke the service provider, because it is not available, and is managing the response itself by carrying out something specified in the SLA of the service itself. You can think of a mock strategy as the response in the ‘worst case SLA’ situation.

Mock strategies can vary in terms of complexity from a simple fixed response message that says that the single feature is unavailable, to a complex algorithm that takes the last ‘good’ result in the user cache and keeps track of the request call to be performed in the future when the system returns to a normal status.

Implementing a mock strategy permits sense to provide a legitimate, if perhaps empty, response so that the requester is not returned an out-of-band error, which could itself instigate a larger system, application or process crash – the classic ‘domino effect’. A well defined mock strategy allows for continuous execution by the calling applications or services under the most extreme circumstances.

go to faq

TerrAria is an italian company focused on providing solutions to the green field of IT. They have adopted sense to provide green services on the cloud, helping companies to monitor pollution levels, power line consumption and other tools to monitor and to respect the environment. The partnership with sense is creating a set of products that let companies startup and implement a plan of savings by installing physical sense green IT devices that act as cloud services in a specific area.

For more detail:

TerrAria s.r.l.
via Zarotto 6
20124 Milano
Italy

tel: +39 0229060612

TerrAria website