Messaging topology

Messaging works in a wide variety of topologies in centralized and distributed environments. Messaging is a scalable solution ranging from an easy-to-deploy single server configuration to a fully scalable multi-server configuration. The flexibility of the multi-server configuration of Messaging allows you to design the topology for a single site as well as multiple site needs. Multiple sites can contain multiple application servers connected to a dedicated storage server.

Site is a set of properties that are defined in the SMI. Each site has its own properties, including access number, extension length, mailbox length, and Auto Attendant. Each user is associated with a site. An application server can support only one site. Location refers to the physical placement of the server, that is its location in a building, city, or country.

Your Messaging network topology is determined by the way your organization has identified its sites.

Typical multi-server, multisite network topologies include sites with:

Distributed application roles
Centralized application roles

Small organizations typically require an easy-to-deploy single-server topology that is ready to grow with the needs of the organization. Large organizations can use the examples discussed in this section as building blocks for their enterprise-wide network architecture, including:

Conforming to an existing network topology
Fitting into centralized data centers
Supporting local survivability networks
Meeting high availability requirements
Supporting disaster recovery requirements