Microsoft’s Office Communications Server (OCS) 2007 is the cornerstone of the company’s unified communications (UC) strategy. OCS is the successor to Live Communications Server (LCS) 2005, but what a difference a couple of years can make. Microsoft’s ambitions for OCS go well beyond the scope of functions provided by LCS, adding highly sophisticated Web conferencing with rich multimedia capabilities, support for group IM conversations (three or more parties), enterprise-level VoIP technology with IP PBX integration, and an enhanced presence infrastructure that supports multiple levels of access to presence information.

However, it’s the “client pieces” that most directly affect the user experience (though it’s dependent on the server technology). Here’s a quick look at the client software and hardware by which users connect to OCS and take advantage of its features.

Office Communicator 2007

Office Communicator 2007 is the primary UC client for the OCS environment. You can install it on a desktop or laptop computer running Windows 2000, Windows Server 2003, Windows XP, or Windows Vista. It integrates with popular Microsoft Office 2007 programs such as Word, PowerPoint, and Excel as well as OneNote and Groove — as well as existing corporate address books. It also integrates with SharePoint Server. With OC 2007, users can communicate via VoIP, video, and instant messaging.

The Communicator client can exchange instant messages with most popular IM services, including MSN, Windows Live, Yahoo, and AOL. Users can make phone calls using either Remote Call Control (RCC), which integrates with the company PBX, or Unified Communications (UC), by which calls go through your computer and IP phone instead of the PBX. With UC, you can make calls from outside the NAT or firewall.

Behavior of incoming phone calls depends on the presence settings. For example, if your state is set to Do Not Disturb, calls go directly to voice mail without ringing on your devices. However, if a contact set at the Team Access level calls, your Communicator device(s) will ring.

Communicator calls will ring all of the recipient’s devices that run Communicator; thus the call could ring on a desktop computer, laptop computer, IP phone, and cell phone. You can make video calls to other users within a corporation or federation, but calls outside the federation or instant messages over the public IM networks don’t support video.

Another handy feature is the ability to create logs of your phone calls — both incoming and outgoing — and your IM sessions, including IM text. For more information, check out the Microsoft Office Communicator 2007 Datasheet.

Office Communicator Web Access

Although the Office Communicator 2007 software offers rich features, it’s not always possible for users to install the client program on the machines they want to use for accessing the OCS server. For this reason, Microsoft also provides a browser-based client, Office Communicator Web Access, that you can use on any computer via its Web browser.

The interface is similar to that of the full Communicator 2007 client. This allows users to stay connected when they only have access to a public computer at a library or kiosk, when using someone else’s computer that doesn’t have the Communicator client installed, or when using a computer that runs a non-Microsoft operating system such as Mac OS X.

With the Web Access version of Office Communicator, you can send instant messages, set and manage presence, and use enhanced conferencing features for multi-user IM sessions. You can’t make phone calls, but you can forward and redirect incoming audio calls.

Supported Web browsers include Internet Explorer 6 SP1 and later, Mozilla Firefox version 2.0 and later, and Apple Safari 2.0.4 and later.

Office Communicator Mobile

Yet another version of the Office Communicator 2007 software is available for users of Windows mobile devices. This is especially handy given today’s increasing dependence on mobile phones for ubiquitous access to corporate resources and communications. Dubbed CoMo (for Communicator Mobile), it can run on handheld computers and smart phones running Windows Mobile 5 or 6. (Note that you must install it in the device’s internal memory; it doesn’t support installation on a storage card). The software requires about seven and a half MB of space on the device.

Once again, the Communicator interface keeps a look and feel that’s similar to that of its siblings, and it offers similar features and functions. There are also special considerations that provide a better experience on the small-sized screen, such as grouping consecutive messages from the same sender together to conserve screen real estate. In addition to conducting IM sessions and setting presence information, you can also make audio calls over Windows Mobile phones using the wireless provider’s network.

Unfortunately, you must install CoMo on the device using ActiveSync 4.2 or above or Vista’s Mobile Device Center. If your device is unable to establish a connection to a PC, as sometimes happens, there’s no support for downloading it directly to the device over the network or installing it from a .cab file transferred to the device via a flash memory card.

Compatible IP “hard phones”

In addition to using the Office Communicator software clients, users can make VoIP calls through OCS using compatible IP phones (i.e., “hard phones”). Microsoft licenses the OCS client to run directly on the SIP phone hardware. These phones feature an interface much like that of the Communicator soft client, with presence indicators by which you can see the status of your contacts.

Such phones are available from Polycom and other vendors. Check out Polycom’s Web site for more information about Polycom IP phones with the embedded Office Communicator client.


There’s been a lot of focus on Office Communications Server 2007 and all of its features, but there’s been a lot less talk about the all-important client end of the equation. You have several different options on how to connect to OCS — whether from your desktop or laptop, from a public computer, from a mobile device, or from a dedicated IP phone.

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