Datasheet

SQL Server 2000 – Particulars and History
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Advantages Disadvantages
Even more upgrades can be done entirely at the server level. Often increases the number of
network connections (which are
frequently the slowest and most
unreliable part of your system).
An increasing number of homogeneous products are
available off-the-shelf – pre-made software is cheap.
Typically there is still
considerably more downtime than
with a host system.
Since only the information to be displayed is sent on the
network (rather than an entire, not yet filtered, data set),
there is little network bandwidth used compared to the
client-centric model. The load may, however, be higher
between the business-logic and data-services systems if
they are on different servers.
The more layers of course, the
more marshalling of data and
requests, and so speed limitations
can creep in.
Allows for (actually encourages) component-based
development, which can increase reusability.
As with 3-tier, more infrastructure
with MTS/COM+ and MSMQ.
Multiple medium servers are often cheaper than one large
server. The separation of business and data services
makes two servers an option.
About .NET
.NET (pronounced "dot net") is a new development strategy being pushed by Microsoft. The latest
updates of Microsoft's server products (including SQL Server 2000) are now being called the .NET
servers. Microsoft will also be producing new versions of Visual Studio that will seek to simplify
implementing .NET.
.NET is, as of this writing, still not a fully rounded-out vision, but it does have a number of proposed
notions that are important for your architecture considerations. For now, what I would say is that it is
important to recognize that all of the .NET servers are increasing their support for XML, and that they
are doing a better job of talking to each other. For your component development, there are changes
coming that will allow you to do an in-place replacement of a component without having to bring down
your server to do it (remember I said, "There is typically still more downtime than a host system" when
talking about n-tier?). This addresses one of the serious problems in development today – how to
perform system upgrades gracefully.
More information will be coming about .NET over the next few years. The first implementations will
only be the beginning of what appears to be a coming revolution in development on the Microsoft
Platform. Microsoft has even indicated that it may take .NET onto Linux (could you imagine?). We'll
see! In the mean time, watch .NET closely – not only for its first arrival, but also as it matures.