Pankaj,
Let me try to answer some of your questions. MS Clustering Service is
included in Windows 2000 Advanced Server. Since MS Clustering Service
depends on some kind o fshared storage between the nodes in the cluster, it
requires more specialized hardware such as a shared storage array (eg, such
as SAN storage). It is useful in situations where state information needs
to be maintained during a communication session such as when accessing a SQL
Server database. So in a sense, MS Clustering Service is a hardware based
clustering solution.
On the other hand, Network Load Balancing (NLB) and Component Load Balancing
(CLB) can be used in situations where state information does not need to be
maintained between connections such as in Web environment. So in situations
where you are using HTTP to access information, each request stands alone.
That is, one HTTP request could be directed to server 1 in a NLB cluster
while the next request could be directed to server 2 in the cluster and so
forth. In some situations, this works because the data on each server in
the cluster is identical. Application Center helps to manage the process of
creating and administering those NLB and CLB clusters. For example,
Application Center helps to replicate the data across the nodes in the
cluster, it also helps with adding and removing nodes from the cluster as
well as distributing incoming requests among the nodes in the cluster.
NLB and CLB and Application Center do not require as much specialized
hardware as MSCS. The nodes in an Application Center cluster do not have to
be identical and they do not need to share a common storage unit.
For Web hosting (including .NET components), NLB and CLB are a better
solution.
For an overview of Application Center, see the following:
http://www.microsoft.com/applicationcenter/evaluation/tour/default.asp
http://www.microsoft.com/applicationcenter/
For a review of clustering technology and options in Windows 2000 see
http://www.microsoft.com/windows2000/technologies/clustering/default.asp
while the following link will contain the latest Microsoft prespective on
clustering technology and options in Windows Server 2003
http://www.microsoft.com/windowsserver2003/technologies/clustering/default.mspx
Hope this helps. Thanks.