Before you begin implementing your chosen topology, there are some important things you must know about the Office Communications Server 2007 R2 requirements and specific topologies. These things are summarized in this topic. Ensure that all of the things in this section have been taken into consideration before you finalize your design.

Infrastructure Considerations

Your Active Directory environment must conform to the supported domains and configurations discussed in Supported Active Directory Topologies.

Office Communications Server 2007 R2 does not support single-labeled domains. For example, a forest with a root domain named localis not supported. For details, see Knowledge Base article 300684, “Information about configuring Windows for domains with single-label DNS names” at http://go.microsoft.com/fwlink/?LinkId=143752 .

Office Communications Server 2007 R2 supports only 64-bit hardware and operating systems for all server roles. For details about the supported hardware and software, see Internal Office Communications Server Component Requirements.

We recommend using the Configuration container in Active Directory Domain Services (AD DS) to store your Office Communications Server global settings. If you are migrating from a previous version of Office Communications Server, run the Office Communications Server 2007 Migration Tool prior to running Schema Prep or performing any other Active Directory preparation tasks.

Ensure you have the necessary hotfixes deployed on each server running Office Communications Server. For details, see Environmental Requirements.

By default, Office Communications Server 2007 R2 is configured to use Transport Layer Security (TLS) for client-to-server connections.

A public key infrastructure (PKI) is required for Office Communications Server 2007 R2. If you do not have an internal PKI infrastructure, you can use a public certification authority (CA) for everything except federation and public IM connectivity, which has the following certificate requirements:

  • For remote user access, federation and public IM connectivity, you must use a certificate issued by a public CA. (Public IM connectivity requires an additional license.)

  • For the MSN network of Internet services and Yahoo!, a Web server certificate is required.

  • For AOL, the certificate must also be configured for client authentication.

For details about certificates, see Certificate Infrastructure Requirements.

Important: Voice Considerations

Power, Network, or Telephone Service Outages

If there is an outage, disruption, or other degradation of the power, network, or telephone services at your location, the voice, IM, presence, and other features of Office Communications Server 2007 R2 and any device connected to Office Communications Server 2007 R2 may not work properly.

Enterprise Voice Depends on Availability of Office Communications Server 2007 R2 and Devices

Voice communications via Office Communications Server 2007 R2 depend upon the availability of the server software and the proper functioning of the voice clients or the hardware phone devices connecting to the server software.

Alternative Means of Accessing Emergency Services

For those locations where you install a voice client (for example, a PC running Office Communicator 2007 R2 or an Office Communicator Phone Edition device), we recommend that you maintain a backup option for users to call emergency services (for example, 911, 112,and 999, depending on the location) in case of a power failure, network connectivity degradation, telephone service outage, or other problem that may inhibit operation of Office Communications Server 2007 R2, Office Communicator 2007 R2, or the Office Communicator Phone Edition devices. Such alternative options could include a telephone connected to a standard PSTN line or a mobile phone.

Emergency Calls and Multi-Line Telephone Systems

The use of a multi-line telephone system (MLTS) may be subject to U.S. (state and/or federal) and foreign MLTS laws that require the MLTS to provide a caller’s telephone number, extension, and/or physical location to applicable emergency services when a caller makes a call to emergency services (for example, when dialing an emergency access number such as 911 or 999). Neither Office Communications Server 2007 R2, Office Communicator 2007 R2, nor Office Communicator Phone Edition devices provide the caller's physical location to emergency services when a caller dials emergency services. Compliance with such MLTS laws is the sole responsibility of the purchaser of Office Communications Server 2007 R2, Office Communicator 2007 R2, and Office Communicator Phone Edition devices.

Conferencing Considerations

General Conferencing Considerations

Running real-time antivirus scanning on the shares that store meeting content, meeting content metadata, and meeting compliance data is not recommended. Doing so can adversely affect performance for Web Conferencing. We recommend the following:

  • Scanning for viruses only when the server has little or no load

  • Enabling and running antivirus protection on client computers at all times

As a best practice, you should also periodically run disk defragmentation on the disk drives where the meeting content is hosted.

Dial-in Conferencing Considerations

You can deploy dial-in conferencing with Enterprise Voice, or without deploying Enterprise Voice.

If you are deploying Enterprise Voice, dial-in conferencing requires that you take the following steps:

  1. Activate the Conferencing Attendant and Conferencing Announcement Service applications during Office Communications Server internal deployment.

  2. Deploy at least one Communicator Web Access server.

  3. Verify location profiles, normalization rules, and server settings to support access number configuration and the user PIN feature.

  4. Configure a global meeting policy that specifies settings for users dialing in from the PSTN.

  5. Obtain toll numbers and toll-free numbers for dial-in access numbers, and then configure the IP/PSTN gateway with those numbers.

  6. Configure Conferencing Attendant.

  7. Deploy the Conferencing Add-in for Microsoft Office Outlook to enable scheduling.

  8. Configure the lineURI attribute for users who are enabled for dial-in conferencing.

  9. Send e-mail to users to announce support for dial-in conferencing.

If your organization does not have Enterprise Voice, you must take the following steps:

  1. Activate the Conferencing Attendant and Conferencing Announcement Service applications during Office Communications Server internal deployment.

  2. Deploy at least one Communicator Web Access server.

  3. Configure location profiles, normalization rules, and server settings to support access number configuration and the user PIN feature.

  4. Configure a global meeting policy that specifies settings for users dialing in from the PSTN.

  5. To enable inbound calls from the PSTN to Conferencing Attendant, either deploy a Mediation Server and an IP/PSTN gateway, or deploy a Mediation Server and enable SIP trunking for carriers.

  6. Obtain toll numbers and toll-free numbers for dial-in access numbers, and then configure the IP/PSTN gateway with those numbers.

  7. Configure Conferencing Attendant.

  8. Deploy the Conferencing Add-in for Microsoft Office Outlook to enable scheduling.

  9. Configure the lineURI attribute for users who are enabled for dial-in conferencing.

  10. Configure a static route from the Office Communications Server 2007 R2 Front End to a Mediation Server. This static route enables users to dial out to PSTN phones from within a conference and to join an audio conference.

  11. Send e-mail to users to announce support for dial-in conferencing.

For details, see Deploying Dial-in Conferencingin the Deploying Office Communications Server 2007 R2 documentation.

Edge Server Considerations

An external DNS SRV record must exist for your Edge Server or array of Edge Servers in order to support discovery of your domain by federated partners. For details, see Certificate Requirements for External User Access.

A reverse HTTP proxy is required to allow remote users to download address book information and expand distribution lists, and download device updates, as well as to allow external users access to meeting content for Web conferences.

If you are using an array of load balanced Edge Servers, the network interfaces of the A/V Edge service must be directly addressable at the IP layer and not behind a network address translator (NAT). If you have a single Edge Server, you can deploy the network interface of the A/V Edge service behind a NAT.

You should only have one inbound mutual TLS (MTLS) listener configured on a Director in your Office Communications Server deployment.

General Office Communications Server Considerations

Office Communications Server Standard Edition requires enough local disk space for meeting content. Particularly if you leverage multimedia functionality of the Live Meeting client, the size required for meeting content can grow large.

Installing any Office Communications Server 2007 R2 role on a global catalog controller or any other domain controller is not supported.

You should use only standard characters (including A–Z, a–z, 0–9, and hyphens) when assigning FQDNs of your Office Communications Servers, Edge Servers, pools, and arrays. Do not use Unicode characters or underscores. Nonstandard characters in an FQDN are often not supported by external DNS and public CAs (when the FQDN must be assigned to the SN in the certificate).

For both Standard Edition servers and an Enterprise pools, you should always place the transaction log files and the database files on separate physical disks that are distinct from any system disks, such as the page file disk. We do not recommend placing these files on system disks.

All Office Communications Servers rely on service accounts. If the passwords to these service accounts expire, the servers cannot operate. Ensure you have a policy in place for updating service account passwords before they expire.

Multihomed network adapters or multiple network adapters configured with more than one default gateway are not supported on individual Office Communications Servers with the exception of Edge Servers.

The service account used by the Web Components Server to allow anonymous access to on-premises conference meetings is set in the IIS metabase. When it expires, no event logs are written by Office Communications Server. You can use the IIS metabase to learn what service account is being used and AD DS to learn the password age of the service account.

User Considerations

Office Communications Server and Office Communicator do not support escaped characters in URIs. You should make sure that all SIP URIs conform to standard SIP grammar and contain no escaped characters.