Client/Server Architecture and Multidimensional Databases: An Overview - Microsoft SQL Server 2008 Analysis Services - page 26

One drawback to the local cube architecture is that your computer must have enough
resources to hold all that data along with the client application, and the power to make
the calculations required by the queries to the cube.

A local cube, otherwise known as one-tier architecture, frees the user from the network—a
handy arrangement when traveling and unable to connect.

Three-Tier Architecture

Once the Internet gained wide usage, a different architecture to make the most of its
advantages was needed. Three-tier architecture, illustrated in Figure 3.3, is the solution
that has been established.

User Admin

Client Client

IIS

XML/A

Server

Data

FIGURE 3.3 In three-tier architecture, the Internet Information Services acts as a middle tier
between the client and the database server.

With this architecture, the client establishes a connection over HTTP with an Internet
server, which then connects to the OLAP server. The OLAP server, usually located on
another computer, sends the response data to the Internet server, which prepares the data
for client consumption in the form of web pages.

The client application can use the same object models for administering the database and
for accessing data as a client application in the two-tier architecture. In addition, a client
application can use web pages and HTTP for those purposes.