Connectivity Framework 4: Connectivity Framework Layer
Delivery refers to the delivery aspects of the data including:
• Best-efforts delivery: An update is sent once, regardless of whether the receivers get it. Also called a fire-and-forget scheme, this is a form of“ at most once” delivery. It is suitable when high-frequency periodic updates need to be distributed in a system and out-oforder or missing updates can be tolerated.
• Reliable delivery: An update is sent and also cached by the sender for later redelivery, in case receiver( s) don’ t get it in a timely fashion. The amount of caching and timing can be configured based on the application and data flow requirements. Acknowledgements from a receiving endpoint can be automatic at the connectivity framework level, or may require explicit response from the application. This is a form of“ at least once delivery”. It is suitable for low frequency status updates, events and notifications and also for commands when updates from a source are expected in-order.
In addition:
• Timeliness is the ability of the connectivity framework to establish end-to-end timing constraints, adaptively reconfigure to either guarantee specified timing or minimize timing violations, and to notify the application if a timing constraint has been violated.
• Ordering is the ability of the connectivity framework to present the data in the order it was produced, or received, and collate updates from different sources in the system.
• Durability is the ability of the connectivity framework to make data available to late joiners, and extend the lifecycle of the data beyond that of the source when so desired, and survive failures in the infrastructure.
• Lifespan is the ability of the connectivity framework to expire stale data.
• Fault tolerance is the ability of the connectivity framework to ensure that redundant connectivity endpoints are properly managed, and appropriate failover mechanisms are in place when an endpoint or a connection is lost.
The underlying transport layer will ultimately bound a connectivity framework’ s performance and scalability limits. The connectivity framework should introduce minimal overhead in providing the data exchange QoS and should have minimal impact on the overall performance and scalability.
4.1.11 DATA SECURITY
A connectivity framework should provide the ability to ensure confidentiality, integrity, authenticity and non-repudiation of the data exchange, when so desired.
The connectivity framework security mechanisms should provide a means to:
• upon discovery, authenticate endpoints before allowing them to participate in a data exchange,
• authorize permissions( read, write) granted to the endpoints participating in a data exchange, to ensure that endpoints cannot write or read data that they have not been given access to,
IIC: PUB: G5: V1.0: PB: 20170228- 31-