Microsoft Sharepoint Products and Technologies Resource Kit eBook

Chapter 4: Windows SharePoint Services Architecture 97
Note The split between front-end and back-end components in Windows
SharePoint Services is a logical one. Physically, the front-end and back-end
components can exist on the same server or on separate servers.
Improvements over SharePoint Team Services
By separating front-end and back-end components, Windows SharePoint Services
has some dramatic improvements in key areas over SharePoint Team Services. Each
of the improvements in the following list affects configuration decisions:
■ Backup. Consolidating all site content and configuration information into
one type of storage simplifies the backup process.
■ Scalability. Windows SharePoint Services can be scaled down to a single
server that contains both front-end and back-end components, or it can be
scaled up to several front-end Web servers accepting requests and gathering
data from multiple back-end database servers.
■ Availability. Multiple front-end Web servers can host the same site content,
allowing others to take over if one fails. Also back-end databases can be clustered
for automatic failover.
■ Integrity of data. Consolidating all the settings and data into one location
and one format protects the data.
■ Customization. Administrators with only an introductory understanding of
Web development, using an HTML editor, can customize the many templates
and properties available in Windows SharePoint Services. For in-depth customizations,
a developer needs to know only ASP.NET Web pages and form controls.
For back-end customizations, a programming knowledge of SQL Server is
needed.
Front-End Web Servers
The front-end Web servers in Windows SharePoint Services use the Web services
provided by Internet Information Services (IIS) in Windows Server 2003. The purpose
of these front-end Web servers is just to service requests from clients. They are
considered stateless because they install only the minimum files and settings needed
to be able to connect to the correct back-end database and retrieve requested site
pages and content.