The document outlines the multi-tier architecture of Microsoft Dynamics CRM, emphasizing the differences between this architecture and traditional client/server models. It highlights the significance of the Microsoft Dynamics CRM platform, which facilitates customization and interaction with the database through CRM-specific APIs, while allowing for extended business logic via workflows and plug-ins. Additionally, it cautions against direct access to the CRM database to avoid data corruption issues.

1. Multi - Tier Architecture
Microsoft Dynamics CRM

2. Agenda
1. Microsoft Dynamics CRM Multi - Tier Architecture
2. Client / Server Architecture
3. Microsoft Dynamics CRM Customization Architecture
4. Domain and Business Logic
5. Database Access

3. In order to effectively customize Microsoft Dynamics CRM,
you must first have good understanding of the application's
architecture. The system's architecture influences how and
where you can customize the system components.
The key to understanding the Microsoft Dynamics CRM
architecture as it relates to customization is the Microsoft
Dynamics CRM platform. One way to understand the value of
the Microsoft Dynamics CRM platform is to contrast it with the
client/server (two-tier) architecture that has been around for
more than two decades

4. Client/Server Architecture
In client/server architecture, most of the application logic is found in the client.
The client processes the information and the server is typically just the database
that processes transactions and stores the data. The services that the database
provides may be unappreciated now that users have become accustomed to
them. However, consider the difficulty that developers may face if they had to
devise their own methods to store, retrieve, and manage data without the
database.

5. The database simplifies much of the complexity that a developer has to deal with
and provides him or her with the means to interact with the data through available
APIs using languages such as Transact-SQL. But the client/server architecture
has many shortcomings and there is only so much that a database designed for
general use can provide.

6. Microsoft Dynamics CRM's Multi-
Tier Architecture

7. Microsoft Dynamics CRM is a web-based application that
uses a multi-tier architecture. This structure provides many
benefits that support scalability, flexibility, and extensibility
that cannot be matched using client/server architecture.

9. Microsoft Dynamics CRM
Customization Architecture
In this multi-tier design, the Microsoft Dynamics CRM platform serves as an
intermediary between the software developer and the database. Just as the
database provides important services in the client/server architecture, the
Microsoft Dynamics CRM platform provides a set of CRM specific APIs that not
only handles interaction with the database, but also provides all the building
blocks for the Microsoft Dynamics CRM application.

10. The parts of the picture marked with a cogindicate places where
the Microsoft Dynamics CRM customizer can interact with the
platform through code, the UI, custom reports etc. This course
concentrates on the part labeled Extendable Application. The
other parts will be described briefly, but detailed treatment is
beyond the scope of this course.
The Microsoft Dynamics CRM platform removes the complexity
that developers may otherwise have to deal with and provides a
rich environment for customizing the application. Because it is
designed specifically for use as a Relationship Management
platform, it can provide more specific features that programmers
can use when they build applications that use it.

11. The Business Entity Components part of the platform is
responsible for creating domain-specific objects. Examples of
domain-specific objects in Microsoft Dynamics CRM include
Contact, Lead, Opportunity, Account, and Business Unit. These
objects are created in response to instructions from the
Application platform, ultimately from the Microsoft Dynamics
standard UI or from customization code.

12. The goal of the Microsoft Dynamics CRM platform is to implement the
service rules by manipulating and combining the underlying domain-specific
objects. The platform accomplishes this by:
1. Controlling access to objects through security.
2. Controlling access to the database through the data access layer.
3. Raising events for workflow processes and custom business logic
implementations.

13. Except for reports, every application that interacts with
Microsoft Dynamics CRM does so through Web services in the
Microsoft Dynamics CRM platform. This includes the Workflow
tools and solutions created by ISVs. In summary, think of the
platform layer as providing the entire infrastructure that is
required to implement a complete Microsoft Dynamics CRM (or
Extended CRM) application.

14. Domain and Business Logic

15. The platform by itself does not impose business-specific logic. This
layer imposes only generic domain constraints. It contains the
components for an application, but by itself is nothing more than a
collection of related objects. However, the interaction between these
domain specific objects implements more extensible business logic
for the organization. You can apply business logic at the platform
through workflow processes and plug-ins; or through the UI using
Dialogs or event scripts on Forms.
1. Microsoft Dynamics CRM Workflow enables you to create
automated business processes at the platform layer. Workflow
processes perform actions based on rules set up by the business.
Workflow processes are triggered by events within Microsoft
Dynamics CRM when specific actions are performed and
specified conditions are met. The Workflows apply the business
logic using built in steps or by allowing developers to add their
own custom code to carry out a step.

16. 2. Plug-ins refer to the ability to create business logic extensions using pre- and
post-plug-ins available in the platform. Plug-ins are extension points made
available by the Microsoft Dynamics CRM platform. There is a published set of
events that a Plug-In can subscribe to. As part of the subscription, a developer
must specify an event handler, which is a segment of customized code that
runs in response to the system event. There are certain parts of the Microsoft
Dynamics CRM application that include business logic that is not found in the
platform and cannot be customized.

17. Example
This is the logic that converts a Lead into a Contact,
Account, and Opportunity. This behavior occurs because
the application interacts with the platform to create these
new objects based on programmatic information stored in
the Lead object. The platform creates the Lead, but the
built-in business logic performed by the application
converts the Lead to a Contact, Account, and Opportunity.

18. Database Access

19. The Microsoft Dynamics CRM platform has a Data Access layer to
handle all interactions between the application and Microsoft SQL
Server, which contains the Microsoft Dynamics CRM
database.Developers must not directly access or update the CRM
database for the following reasons:
1. It introduces the opportunity for invalid or corrupt data to be
added to the database, which in turn can cause the Microsoft
Dynamics CRM platform to function incorrectly.