Microsoft Office Communications Server 2007 R2 is an enterprise server product that combines corporate instant messaging (IM), presence, federation, conferencing, group chat, group response, an attendant console, and telephony (Voice over IP, or VoIP) in a fully integrated Unified Communications (UC) solution. It can integrate with existing Private Branch eXchange (PBX) infrastructures to leverage the investment in communications that organizations have already made.
If the customer has invested in Microsoft Exchange Server 2007, integration with Exchange enhances the overall offering with the ability to enable Exchange to act as a voice mail solution—the Exchange user can receive voice mail anywhere that she can receive Exchange mail. Adding Speech Server 2007 further enhances the overall offering and provides a rich development platform for extending beyond the feature sets delivered in the box.
Office Communications Server and Exchange together are referred to as Unified Communications (UC) and present a compelling solution for the small, medium, and large customer to augment or even replace an existing legacy PBX.
Office Communications Server 2007 R2 is available in two editions: Standard Edition (SE) and Enterprise Edition (EE). The SE Server is a single-server configuration, whereas the EE pool is a multiserver configuration that provides the same functionality as the SE Server with higher scalability and reliability.
An Enterprise front-end pool scales by building servers that are load balanced and provide enough resources for the required load for each of the necessary roles. Determining how many front-end servers per Enterprise pool will be needed is a planning exercise and is covered in depth in Chapter 14. Planning is also made much easier because of the planning tool that uses metrics defined by the Office Communications product group. This tool assists in defining the number and configuration of servers to achieve the desired technical goals. This tool is discussed in Chapter 14 as well.
Both the SE and EE contain a number of server roles. Some must be deployed, and others are available upon installation of an Enterprise pool or SE Server.
The server roles located on an Enterprise pool front-end server or SE Server are:
IM Conferencing and Presence
Telephony Conferencing Server
Unified Communications Application Server (UCAS)
Web Components Server (requires an installation of Internet Information Server 6.x or 7.x)
Web Conferencing Server
Audio/Video (A/V) Conferencing Server
Application Sharing Conferencing Server
Note
The list of server roles on the front end assume that you are using the Setup Wizard. There are options to deploy separate Web Component, Web Conferencing, A/V Conferencing, and Application Sharing Servers, but only through the LCSCmd.exe tool. This is what is known as an expanded topology.
A dedicated SQL Server back end is required for the EE. For high availability, the SQL Server can be configured as an active/passive cluster. SE deploys Microsoft SQL Server Express 2005 as part of the SE installation and cannot be clustered.
Optional servers that can be deployed for further function, performance, and compliance reasons are:
Archiving. Enables IM message logging and includes the ability to collect Call Detail Records (CDRs)
Monitoring. Includes Quality of Experience (QoE)
Group Chat Server. Users can create and maintain a chat room where the discussions, files, and other collaboration that take place in the room are retained and are persistent, as well as secured to only the invited members of the room.
To enable Office Communications Server 2007 R2 for telephony, a Mediation Server is usually required to function as an intermediate between Office Communications Servers and the media gateway. Office Communications Server 2007 R2 also supports direct connectivity with a supported Internet Protocol (IP) PBX, called Direct Session Initiation Protocol (SIP). Office Communications Server 2007 R2 supports four different types of telephony configurations: Enterprise Voice (see Chapter 11), Remote Call Control (RCC; see Chapter 9), dual forking (see Chapter 10), and RCC with dual forking (see Chapter 10).
Organizations can enable remote access for their users and federation with other organizations that have deployed Microsoft Live Communications Server 2005 Service Pack 1 (SP1), Microsoft Office Communications Server 2007, and Office Communications Server 2007 R2. To configure the Office Communications Server 2007 R2 Server for remote access and federation, an Edge Server is deployed in the perimeter network.
All roles will run on each of the consolidated Edge Servers, and more than one server is positioned behind hardware load balancers (HLBs). Multiple Edge Servers behind a hardware load balancer provide two direct benefits:
Scale. To provide more processing power to service more connections for the front-end pool servers
High availability. In the event a server should fail, more than one server provides for failover and recovery