Communicator Web Access Server Role

Communicator Web
Access (2007 release) is an Office Communications Server 2007 server
role that is now available on the Office Communications Server 2007 CD
and no longer downloadable from the web. Communicator Web Access (CWA)
addresses a specific customer need that is not satisfied by any other
Office Communications Server 2007 server role.  CWA provides a server scale client for Office Communications Server that targets the following 3 platforms:


  • Locked-down
    Windows – these are IT administered Windows computers, and therefore
    users cannot install Office Communicator 2007 to sign-in to Office
    Communications Server. Such users can still sign-in to Office
    Communications Server via CWA.
  • Non-Windows
    platforms – computers not running a Windows operating system cannot
    install Office Communicator 2007. Such users can use CWA.
  • Mobile
    client platforms – mobile devices with web browsing capability and
    compatible with AJAX technology or a custom client can potentially
    sign-in to Office Communications Server using CWA. 

Communicator Web Access
(2007 release) offers a zero install web client experience for Office
Communications Server 2007 for those users who cannot use Office
Communicator 2007. Users enabled for Office Communications must
authenticate to CWA in order to sign-in to Office Communications Server
(see Figure 1).  CWA supports 3 types of authentication
methods: Integrated Windows Authentication, Forms-based Authentication,
and Custom Authentication.

Figure 1

Because the UI
similarities between CWA and Office Communicator are so close, CWA also
makes for the perfect companion to Office Communicator because users do
not need to adapt to a different user experience when switching between
the two clients (see Figure 2).

Figure 2

Although CWA does not
currently support VoIP functionality, users enabled for Enterprise Voice
can get notified of incoming calls and redirect calls to a different
number such as a cell phone.  Alternatively, users can
configure to have incoming calls simultaneously ring a different number
in addition to their work number or forward calls from their work number
to a different number anywhere they can sign-in to Office
Communications Server (see Figure 3).


Figure 3

For a comparison between Communicator Web Access (2007 release) and Office Communicator 2007, see table 2.


Table 1

In addition to offering a
server-scale client solution out-of-the-box, CWA offers a
cross-platform, cross-browser API set called, Unified Communications
AJAX APIs, for the ISV community to integrate Unified Communications
client functionality into web server applications such as web portals,
line of business web applications, widgets and gadgets. This API makes
it possible to create server-side Web 2.0 mashups.

The UC AJAX APIs are XML based.  This
makes it very easy for developers familiar with XML but unfamiliar with
the SIP and SIMPLE protocol, which Office Communications Server 2007 is
based on, to quickly build Instant Messaging and Presence functionality
into existing and new web applications.  CWA uses two
secure connections (HTTPS) per client browser, one connection is used as
the signaling channel to send requests to CWA, and the other connection
is called the data channel used by CWA to send events to the client
(see Figure 4).

Figure 4

With CWA’s Custom
Authentication functionality, you can leverage Microsoft ISA Server 2006
to provide users a single sign-on experience (and avoid all those pesky
logon requests) or enforce two-factor authentication access to Office
Communications Server 2007 through custom development.

Microsoft makes available documentation and samples to help the ISV community build applications using the UC AJAX APIs.  Find out more and download the UC AJAX SDK at:


- Rui Maximo
Sr. Program Manager - OCS

Published Monday, November 12, 2007 11:27 AM

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Comments (1)
  1. elizabeth ramirez guzman says:

    hola tengo problemas para accesar al communicator

Comments are closed.

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