R

Recipient Update service

Part of the Exchange System Attendant, this service is responsible for keeping address lists up-to-date and creating proxy addresses for users.

remote procedure calls (RPC)

A reliable synchronous protocol that allows a program on one computer to execute a program on another computer. Outlook clients use MAPI RPCs for accessing mailboxes and public folders.

resource

In real-time collaboration, a user object in Active Directory that represents a facility. Resources are stored in the System\Exchange organizational unit in Active Directory.

request for comments (RFC)

RFCs are a series of notes about the Internet. Anyone can submit an RFC and, if an RFC gains enough support, the RFC might become an Internet standard. Each RFC is designated by an RFC number. Once published, an RFC never changes. Modifications to an original RFC are assigned a new RFC number.

RGC

See Routing Group Connector (RGC).

rich text file

One of the two files that make up an Exchange database. The rich text file (ending in .RTF) holds e-mail messages and MAPI content, and the native content file or streaming file (ending in .STM) holds all non-MAPI information. The term is also used to describe a file formatted according to a formatting standard defined by Microsoft. RTF files are actually ASCII files with special commands embedded in them to indicate formatting.

routing group

A collection of Exchange servers that can transfer messaging data to one another in a single hop without going through a bridgehead server. In general, Exchange servers within a single routing group are connected by high- bandwidth links. Connectivity among servers in a routing group is based entirely on SMTP.

Routing Group Connector (RGC)

A connector in Exchange Server 2003 that connects routing groups to one another. A Routing Group Connector is unidirectional and can have separate configuration properties (such as allowable message types over the connection). Routing Group Connectors use the concept of local and remote bridgeheads to dictate which servers in the routing groups can communicate over the link. The underlying message transport for a Routing Group Connector is either SMTP or RPC, and it uses link state information to route messages efficiently.

routing service

A component in Exchange that builds link state information.

RPC

See remote procedure call (RPC).