Unity Notification Framework architecture

Is this technology based (e.g. SNS) or should we investigate a standard for this (e.g. OGC Pub/Sub). 

Requires:

* Representative User Stories
* Architecture
* Message Schema (convince me it's not CNM or an extension of that)
* Message Attributes (e.g. SNS Filterables)
* Deployable as a part of Unity or works as a 'stand alone component (e.g. non-monolith, AWS Quikstart)