In this my first 'technical' post on this blog I want to simply introduce Cortexa's hosted learning environment with a short high level overview of what Nereus is, the architecture design applied and the technologies used.

Although I plan for many of the technical posts on this blog to be generic to programming and systems architecture, they will often be based on our experience with designing and developing the Nereus learning solution and I thought this would be a useful reference for future posts.

So what is Nereus?

I have often found it a little difficult to describe our Nereus environment/solution without sounding like I have swallowed a marketing "how to" book, so apologies in advance and here goes...

Nereus is an integrated, content managed, hosted learning environment allowing tracking and management of individual learner’s activity across an organisation. The Nereus solution brings together e-learning delivery and management, classroom and distance learning management, and knowledge base and collaboration features such as document libraries, discussions, blogs and wikis.

See I warned you! It may sound like marketing spiel but it does aptly describe the concept of Nereus.

The current Nereus offering consists primarily of the following elements:

• Nereus Framework
  The Nereus Framework is the core engine of Nereus and effectively comprises of the data, business and service layers of Nereus' multitier architecture.
  
• Course APIs
  In addition to supporting aspects of the SCORM specification, Nereus has it's own course API for allowing learning module or resource usage to be tracked and analysed. This API is used by all Cortexa developed learning content as well as several third party vendors that target Nereus Academies.
  
• Nereus Portal (also referred to as a Nereus Academies)
  Users of Nereus primarily access functionality through the Nereus Portal which is a web application that provides the web based user interface. Although the portal is a single web application it supports any number of individual academies each of which have their own sand boxed data and unique UI design and customisation.

Sample Nereus Academies (Nereus portal instances)

Nereus Architecture

Nereus is designed with a multitier architecture where we have four distinct layers which can be optionally distributed over three tiers (physical boundaries); Presentation Tier, Service+Business Tier and Data Tier. Below you can see a diagram representing our multitier architecture.

Nereus Architecture Diagram

This service architecture has the standard data, business and presentation layers you see in many a multitier design but with our third generation of Nereus, soon to be launched, we have added a Service Layer which incorporates SOA (Service-Oriented Architecture) into the design (we have also re-factored the business and presentation layers considerably to take advantage).

This new service layer enables us to have a common service-based interface to the Nereus Framework for all of our own client applications (i.e. Nereus Portal, internal admin tools and future desktop apps and tools) as well as providing selected functionality to our customers IT infrastructures (i.e. Peoplesoft or SAP integration) and to any third parties that we may partner with in the future.

Technologies & Tools

Finally a quick look at some of the technologies and tools used in the development of our Nereus solution (for Nereus V3).

• Windows Server 2008 + IIS7
• .NET Framework 3.5 (.NET 2.0 used in previous versions)
• Windows Communication Foundation (WCF)
• Enterprise Library (Jan 2005)
• ASP.NET 3.5
• ASP.NET Ajax (inc. ASP.NET AJAX Control Toolkit)
• SQL Server 2005 (utilising Stored Procedures)
• Visual Studio Team System 2008 Development Edition
• Team Foundation Server 2008
• Written largely in C#