Overview of the RPC Protocol

SharePoint™ Team Services from Microsoft® and Microsoft FrontPage® Server Extensions 2002 are a set of programs that work in conjunction with Microsoft Internet Information Server (IIS) to support administering, authoring, and browsing a Web site.

Web sites based on SharePoint Team Services give you features beyond those of FrontPage Server Extensions-based Web sites. SharePoint team Web sites enable groups to share files, participate in discussions, and communicate all kinds of information. 

Team members with the proper permissions can create fully working Web sites in seconds, even if they don't know anything about Web authoring. The Web sites are easy to expand and keep up-to-date, because SharePoint team Web sites have easy-to-use forms for creating new pages and automatically update the site navigation links when a new page is added. For example, if a team member adds a document library to the site, a link is automatically added to it on the home page. Team members can create new Web sites and customize them using a Web browser. Using SharePoint Team Services-compatible programs, such as those in Microsoft Office® XP, team members can work with files directly on the team Web site, or even create a new team Web site.

SharePoint Team Services and the FrontPage Server Extensions Remote Procedure Call (RPC) protocol governs the exchange of information between any client and the Web server. This communications protocol is layered on top of the same HTTP protocol that Web browsers use to interact with a Web server.

The RPC protocol uses the HTTP POST request to send methods (see Decoded Method) to SharePoint Team Services and the FrontPage Server Extensions. These requests enable the client to request documents, update Tasks lists, add new authors, and so on. The return values contain any requested information to the client in the form of an HTML document.

The RPC protocol reduces the number of costly file transfers over the Internet. When a client author opens a web from a Web server running SharePoint Team Services or FrontPage Server Extensions, information about the web, such as its hyperlink map, is downloaded to the client machine so that the client can display the information. However, the full set of pages and other files that comprise the web remain on the Web server.

A page is downloaded over the Internet only when it is opened for editing in a client application. This is a very efficient mechanism: an entire Web site can be changed directly on a Web server by downloading and editing a single file. For example, the Include Page component in Microsoft FrontPage can be used to include a company's address and phone number in a footer on every page of the company's Web site. If the phone number changes, only the page containing the address and phone number need be downloaded and opened using the client. Once the phone number is updated and the page is saved, the phone number is re-included on all other pages on the Web server by the server extensions.

SharePoint Team Services and FrontPage Server Extensions  can be used with the Microsoft Visual SourceSafe® version control system, which allows files to be checked in and out of the Web server. SharePoint Team Services and FrontPage Server Extensions also support "light" check in and check out, which do not require Visual SourceSafe, but still protect authors from overwriting files that are currently being used by another author.