Databases Reference
In-Depth Information
J2EE and .NET application servers have evolved a great deal in the last decade and are
the clear inheritors of the TP monitor legacy for today's
N
-tier systems. Different com‐
panies have different standards and preferences—the proprietary nature of .NET leads
some firms to J2EE, while others prefer the tight integration of Microsoft's offerings. A
detailed discussion of the relative merits of J2EE and .NET, and application server tech‐
nology in general, is beyond the scope of this topic. Suffice to say that application servers
play an extremely important role in today's systems environment, and database man‐
agement personnel need to understand
N
-tier systems architecture.
Figure 9-4
depicts an
N
-tier system with a client, web server, application server, and
DBMS server.
Figure 9-4. An N-tier system
The Grid
Oracle Database 10
g
introduced focus on another architecture variation—grid com‐
puting. The actual topology of the grid is not relevant to the discussion in this chapter,
because the point of the grid is to provide an extremely simple user interface that trans‐
parently connects to a highly flexible source of computing power. In this way, the grid
gives IT departments the ability to achieve the benefits of more complex architectures
while not imposing undue complexity on users, and OLTP applications are deployed
using grid computing resources.
In a similar fashion, the topology of underlying resources in the cloud are not visible
to consumers, and the benefit of using complex architectures through a simple use
model is one of the key features of cloud computing, which is the subject of
Chapter 15
.
