Configuring a Routing Topology


This section explains the planning, concepts, and procedures that are involved in configuring your routing topology. It contains the following topics:


If you are operating Microsoft® Exchange Server on a single server, most of the topics about routing groups do not apply to your organization. However, you may find these topics useful if you are planning to expand your messaging system to support multiple servers.

  • General Planning Considerations

    This topic explains the information that you need to gather before configuring your routing topology, and the variables that influence your routing topology.

  • Common Routing Topologies

    This topic presents the two common routing topologies, a centralized routing topology and a distributed routing topology, and explains when these topologies are typically used.

  • Defining Routing Groups

    This topic explains how to create routing groups, routing group connectors, and how to connect routing groups.

  • Understanding Connector Scope and Restrictions

    This topic explains the decisions that are involved in using connector scope and restrictions.

  • Designating a Routing Group Master

    This topic explains what the routing group master is, how it works, and the criteria for designating a routing group master.

  • Advanced Routing Configuration

    This topic presents advanced routing configuration topics. It discusses how to use connectors for load balancing and failover, and how to suppress link state traffic.

General Planning Considerations

A well-designed routing topology is essential for efficient and reliable message flow. Before you design your routing topology, be aware of the following limitations for a single Exchange organization. A single Exchange organization cannot exceed:

  • More than 1,000 administrative groups.

  • More than 1,000 servers.

Before you configure your routing topology, you must perform a detailed assessment of your current environment, taking into account the following variables:

  • Network topology and users in each location

    The connectivity between locations and the available bandwidth, with consideration to the applications currently using the network and future projects requiring the existing bandwidth.

  • User number, location, and usage patterns

    The number of users sending messages across the network is an important consideration. Additionally, how users are distributed and whether they communicate primarily with other users in their location, or with other users in different locations. Also, you should consider the size of messages that are sent by users in specific locations. For example, a design department may send messages with attachments of large graphic files to various business partners. This traffic will have a greater effect on the network than traffic from a department that sends very few attachments across the network.

  • Type of applications used by your company

    The types of applications that are used by the network and the peak usage times for the network.

  • Data center locations

    The location of your data centers and the available connectivity to regional offices and other data centers.

  • Free/busy requirements

    The use of current free/busy information in different geographical locations. Public folder replication includes the replication of free/busy information. Do users in different geographical locations require current free/busy information for users outside of their geographical locations, or do users generally need current information only for users within their location?

  • Current Microsoft Active Directory® directory service design

    The placement of global catalog servers and domain controllers, the way in which your Microsoft Windows® sites are designed, and how they correspond to your routing groups.