IIS 6.0 Services

Applies To: Windows Server 2003, Windows Server 2003 with SP1

IIS 6.0 offers four Internet services that you can use to create sites or virtual servers, configure properties and security settings, and set up components to customize your system.

When you install IIS 6.0 on a computer that does not contain an earlier version of IIS, IIS 6.0 automatically installs the following two services:

• The WWW service, which hosts Internet and intranet content.

• The IIS Admin service, which manages the IIS metabase.

You can also choose to install one or more of the following services:

• The FTP service for hosting sites from which users can upload and download files.

• The NNTP service for hosting discussion groups.

• The SMTP service for sending and receiving e-mail messages.

Table 2.2 lists the IIS services, their core components, and their service hosts.

Table 2.2 Basic Services Provided by IIS 6.0

World Wide Web Publishing Service

The World Wide Web Publishing Service (WWW service) provides Web publishing for IIS, connecting client HTTP requests to Web sites running on an IIS-based Web server.

The WWW service manages and configures the IIS core components that process HTTP requests. These core components include the HTTP protocol stack (HTTP.sys) and the worker processes.

The WWW service includes these subcomponents: Active Server Pages (ASP), Internet Data Connector, Remote Administration (HTML), Remote Desktop Web Connection, server-side includes (SSI), Web Distributed Authoring and Versioning (WebDAV) publishing, and ASP.NET.

FTP Service

IIS provides an FTP service, which you can use to allow users on remote computer systems to copy files to and from your server on a network that uses TCP/IP. The IIS FTP service is an implementation of the File Transfer Protocol, RFC 959, File Transfer Protocol (FTP), and several extensions. The FTP protocol is implemented on top of TCP, which ensures that file transfers are complete and that data transfer is accurate.

You can deploy the FTP service across an arbitrary number of front-end and back-end servers, which increases reliability and availability. By adding virtual directories and servers, you can easily scale FTP without affecting end users.

In IIS 6.0, the FTP service allows you to isolate users at the site level, a feature known as FTP user isolation, to help administrators secure and commercialize their Internet sites. Because of the easy availability and wide adoption of FTP, Internet service providers (ISPs) and application service providers (ASPs) traditionally have used FTP to upload their Web content. IIS 6.0 allows the isolation of users into their own directory, thus preventing users from viewing or overwriting other users Web content. The user's top-level directory appears as the root of the FTP site, thus restricting access by not allowing users to navigate farther up the directory tree or across to other users home directories. Within the users own site, the user can create, modify, or delete files and folders.

SMTP Service

The SMTP service in IIS processes messages by using the Simple Mail Transfer Protocol (SMTP), which is a TCP/IP protocol that is used to send and receive messages from one computer to another on a network. This protocol is used in intranets and on the Internet to route e-mail.

SMTP is the Internet standard for transporting and delivering electronic messages. Based on specifications in RFCs 2821 and 2822, Microsoft SMTP service is included in the Windows Server 2003 operating system. In Windows Server 2003, the SMTP service is actually a component of IIS and runs as part of Inetinfo.exe. Windows Server 2003 uses SMTP as its native transport protocol to route all messages internally and externally. SMTP is also the default transport for Microsoft® Exchange 2000 Server.

The SMTP component of IIS can send or receive SMTP e-mail messages. You can program the server to automatically send messages in response to events — for example, to confirm a successful form submission by a user. You can also use SMTP to receive messages — for example, to collect feedback from Web site customers.

SMTP does not provide a complete e-mail service. To obtain complete e-mail services for your users, use Microsoft® Exchange Server. For more information about Exchange Server, see the Microsoft Exchange Server TechCenter.

NNTP Service

IIS provides a Network News Transfer Protocol (NNTP) service, which you can use to distribute network news messages to NNTP servers and to NNTP clients (news readers) on the Internet. NNTP provides for the distribution, inquiry, retrieval, and posting of news articles by using a reliable stream-based transmission of news on the Internet. With NNTP, news articles are stored on a server in a central database from which users select specific items to read. Indexing, cross-referencing, and expiration of aged messages also are provided.

You can host NNTP local discussion groups on a single computer. Because this feature complies fully with the NNTP protocol, users can use any NNTP client to participate in the newsgroup discussions. The IIS NNTP service does not support news feeds or replication. To use news feeds or to replicate a newsgroup across multiple computers, use Microsoft Exchange Server.

IIS Admin Service

IIS Admin service is a Windows Server 2003 service that manages the IIS metabase. The metabase stores IIS configuration data in a plaintext XML file that you can read and edit by using common text editors. IIS Admin service makes metabase data available to other applications, including the core components of IIS, applications built on IIS, and applications that are independent of IIS, such as management or monitoring tools. For more information about the IIS metabase, see The IIS Metabase and Working with the Metabase.