Hi,
Here is my understanding of this topic, based on our past experience.
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SAS Real-Time Decision Manager (“SAS RTDM”) is perhaps the easiest to define: it's SAS product that allows executing real-time decisions according to the decision flow business logic configured in an intuitive diagram-based UI - SAS Customer Intelligence Studio. The product has well-defined capabilities (described in SAS RTDM User Guide / Admin Guide) - what can you do in these diagrams, what nodes are available to be used, how custom nodes can be defined, how diagrams are deployed for execution on runtime environments, what are the format of SOAP and REST web services being implemented by deploying said diagrams, etc.
The original purpose of SAS RTDM product is customer intelligence and interactive marketing - implement smart real-time decisions on offer assignment during interactions with customers in real-time and online channels. Hence, SAS RTDM is part of a SAS Customer Intelligence suite - often sold and used alongside SAS Marketing Automation and other products in that suite (SAS Marketing Optimization, etc), contains lots of functionality specifically designed for marketing use cases (offer assignment), uses shared Common Data Model with Campaign, Contact and Response history, etc. Even the basic terminology is heavily marketing-influenced: "SAS Customer Intelligence Studio" is its UI, the main thing you design is called "Campaigns", etc.
However, as the product itself is so powerful and flexible, that it is sometimes used for other general enterprise decisioning use cases that don't have to do with marketing offers. Like credit decisions (loan origination) in banks, dynamic pricing and claims processing decisions in insurances, etc. In this case, some marketing-specific functionality is just not being used, but the diagram-based decisioning capabilities are leveraged to the fullest extent.
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SAS Decision Manager is a different software suite from SAS that combines multiple products to work together for the similar purpose but primarily outside of marketing / customer intelligence context: automate enterprise "decisions" according to flexible business rules and analytical models, as defined by the business users.
Its documentation is freely available online, for an older version and newer version (Viya-based). The older version included a "Decision Builder" rules-based UI where you could combine "Rule Flows" (as defined in SAS Business Rules Manager - SAS BRM), Models (as defined in SAS Model Manager), and branching "Conditions" to navigate between those. The resulting decision could be published for real-time execution via REST API through SAS MAS, or published to be used in batch processing through SAS Data Integration Studio and other tools (as both business rule flows, and models logic can mostly be expressed with Data Steps / DS2 steps). The toolset is use case agnostic - there is no marketing or customer-intelligence specific functionality or terminology. It also included SAS Workflow Studio used to define and implement business rules, models, and decisions and business rules version pipelines: preparation, approval and deployment workflows.
From the functionality standpoint, there is a lot of overlaps and even partial reusability between SAS RTDM and SAS Decision Manager (older pre-Viya version). For example, SAS RTDM diagrams can also apply same SAS BRM Rule Sets (through the "Business Rule" node)., SAS RTDM diagrams can also apply same SAS Model Manager published models (through the "Score") node. Everything you can do in terms of a decision logic in Decision Manager, you can also do in SAS RTDM - and in SAS RTDM you can arguably even do more than that (many of its capabilities are not easily replicated in just the Decision Manager alone). But in SAS RTDM, the business logic acceptance and deployment process is not that advanced (there are no rigid complex workflows) - as it's generally not needed for marketing offers decisioning. Also, SAS RTDM can't produce batch code that is efficient in batch processing over millions of records - since in SAS's approach it was being done by SAS Marketing Automation batch campaigns.
The newer Viya-based version of SAS Decision Manager (5.1) is very different technologically under the hood. For example, the business rules functionality is similar - but it's no longer SAS Business Rules Manager rule sets - so now you can't reuse those in SAS RTDM, etc. But is intended to fulfill the same vision and approach as the original SAS Decision Manager offering. It is now also offering a simple diagram-based decision flow UI (somewhat similar to what there is in SAS RTDM), so chances are high that it may continue being developed that way in the future and obtain more of a diagram-based functionality of SAS RTDM that is not otherwise available in older SAS Decision Manager. Of course, it's just a speculation and we don't know for certain.
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SAS Decision Services is more or less another name for SAS RTDM - it can be seen in several under-the-hood places in SAS RTDM (in SAS Management Console, and in some application files, in the logs, etc). It appears that SAS may have at times also positioned SAS RTDM under that name (SAS Decision Services) for non-marketing use cases, probably it was there before SAS Decision Manager offering was assembled together? Hard to say, it's just a guess. In any case, this name seems to have fallen out of usage, at least like it appears outside of SAS organization (to its partners like us).
Feel free to reach back into a direct message if you feel I can help you further with this topic. Will be happy to help.
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Dmitriy Alergant, Tier One Analytics
