Mobile access to Exchange Server is increasingly popular. Mail-enabled mobile devices such as Research In Motion's (RIM's) BlackBerry handheld devices are becoming more common and are offering more useful functionality. Exchange Server 2003's new Outlook Mobile Access (OMA) and Exchange Server ActiveSync components add significant mobile functionality to Exchange 2003 servers, enabling full-featured mobile access for users of a variety of devices (ranging from compatible Web browsers to cell phones to Pocket Outlook devices). Both components offer mobile-device access to Exchange data, but OMA and Exchange ActiveSync differ in architecture and functionality.
OMA is the successor to Microsoft Mobile Information Server (MIS) 2002. OMA is a separate service that runs on your Exchange servers. (Like Outlook Web Access--OWA--OMA is published in a Microsoft IIS virtual directory.) OMA publishes Exchange data to limited-function devices that can act as browsers and that use the Wireless Application Protocol (WAP) or Extensible HTML (XHTML). Such devices include mobile phones, wireless PDAs, and iMode devices (a special class of devices available primarily in Japan). OMA lets users access the Inbox, Calendar, Contacts, and Tasks folders; create new messages, contacts, and tasks; and browse or search the Global Address List (GAL). The service is by no means a replacement for OWA or Outlook, but OMA is surprisingly useful on devices that support alternative methods of text input such as T9 or thumb keyboards.
Exchange ActiveSync is a different animal. This component lets users wirelessly synchronize a Pocket Outlook device (including Motorola's MPx200, devices running Microsoft Pocket PC Phone Edition, and wireless Pocket PC 2002 devices) with Exchange. Whereas OMA renders Exchange Store data in a form that the handheld device can display, Exchange ActiveSync simply retrieves native Exchange data (the local copy of Pocket Outlook renders the data). Exchange ActiveSync also enables access to attachments, which OMA can't handle. In addition to Exchange ActiveSync's native functionality, users of wireless Windows Mobile 2003 devices can get automatic over-the-air notification of new messages (the Exchange server sends an alert to the user's mobile carrier, which forwards the alert to the mobile device, which initiates a synchronization to access the new message). Together, Exchange ActiveSync and Pocket Outlook give users many of the same capabilities as the full version of Outlook: access to folders within the Inbox, scheduled or on-demand synchronization, and the ability to download only the headers of new messages by default (with the ability to retrieve message bodies manually).
The combination of OMA and Exchange ActiveSync supports a range of devices, including popular cell phones such as Sony Ericsson's T68i and P800. Microsoft is committed to releasing Device Update (DU) packages that add support for even more devices; for a complete list of supported devices, see the Microsoft article "Overview of Mobile Devices That Are Supported by Outlook Mobile Access in Exchange Server 2003" ( http://support.microsoft.com/?kbid=821835 ).
Of course, widespread mobile access carries a unique set of challenges and problems, some of which I'll explore in future columns. As soon as I get hold of a new Windows Mobile 2003 Windows Powered Smartphone, I'll test the product and report about that as well. In the meantime, I'll keep you updated as I experiment with OMA and Exchange ActiveSync.