Leveraging Exchange ActiveSync for PDA Mobile Communications

Pocket PC devices have become more popular over the past couple of years , not only because more devices now include mobile Windows, but also because the ability to fully synchronize calendar, contacts, and other Outlook information makes the functionality more useable. Instead of having to convert contacts, appointments, or messages between disparate applications or learning new tools, a Pocet PC device uses a similar interface to natively synchronize content.

Additionally, because the interface and content remain in native formats, not only do users have the ability to access their email, calendar, and contact information, but they also have full access to other Outlook folder content, such as subfolders and attachments. So if users have managed their Outlook folders with custom containers ”organizing information by client, project, or chronological date, or other method ”those folders also can be accessed and synchronized.

Additional improvements in the Exchange ActiveSync with Exchange 2003 include the ability to prevent users from pushing everything, but customizing information synchronization by preventing the sync of nonessential messages, attachments, or content. This offers the ability to create filters and define characteristics on message downloads, decreasing the traffic between the mobile device and the server. Although information can be filtered to prevent the automatic synchronization of this content, Exchange 2003 does provide the ability for the user to manually request the attachment or other filtered information to be transmitted. So the user has the ability to focus bandwidth and information access as effectively as possible.

Flexibility of Information Synchronization

When synchronizing information between Exchange 2003 and a Pocet PC-enabled device, the device can be connected by a variety of different connectivity methods . The device can be connected through a traditional cradle using the network connectivity of the host system to synchronize with Exchange. A Pocet PC-enabled device can be directly connected to a network using an Ethernet adapter in the device. Through the Ethernet adapter, the device can communicate with the Exchange 2003 server.

A Pocet PC-enabled device can also communicate over wireless methods, and can have a wireless LAN adapter using 802.11b, 802.11a, 802.1x, Bluetooth, or infrared. A wireless LAN connection truly disconnects the user from a cradle or physical connection to the network. This provides mobility for the user to access Exchange content anywhere within an office or campus facility. With wireless mobility, the user can keep calendar appointments, email messages, and other up-to-date information accurate and accessible.

When the device is not within the range of a local area network wireless connection, more mobile public network connectivity can extend real-time synchronization regionally , nationally, or globally. Using cellular phone, PCS, GPRS, 1xRTT, GSM, and other public network systems, a properly equipped Pocet PC device can enable users to synchronize their mail, calendar, contact, and other information anytime and anywhere.

Customizing Synchronization Characteristics

Pocket PC-enabled devices can synchronize folders and subfolders with Exchange and have the capability of filtering and truncating information that is sent and received by the device. Customization of sync characteristics also includes the ability to delete messages or information on the device and have those changes synchronized up to the Exchange server to be deleted on the server copy of the information. The same applies to information that might be deleted using Outlook Web Access, using the full Outlook client software, or by other Exchange client applications that replicate the changes back down to the Pocet PC device. Having full control over the synchronization characteristics, along with the ability to delete in one place what is replicated to all user devices, drastically improves the ability of users to control information regardless of what device they use to access their Exchange information.

Improving Mobile Performance

As a user accesses Exchange using a variety of different mobile devices, there are times that the bandwidth availability between the Exchange server and the device is grossly limited. Although local area network connections have commonly relied on 100MB, speeds and thus the opening and accessing of large 2MB attachments or 10MB files go unnoticed. However, when a mobile user tries to synchronize a 2MB file over a 9600 baud mobile connection, the file could take 20 “30 minutes to transfer, preventing the user from getting urgent emails or other messages during the transfer. Also, many wireless service providers charge based on packets transferred, so the automatic sending and receiving of large attachments could be very expensive. Exchange ActiveSync, included with Exchange 2003, enables the user to choose whether to synchronize attachments.

With Exchange ActiveSync, there is also a smart reply and smart forward function that prevents the need to have an attachment received or sent to the mobile device in order for the user to reply or forward the attachment. For example, a user might receive a large Word document to review. Rather than receiving the document, reviewing it, and then forwarding it to someone where the large attachment would be received and then sent by the mobile device, Exchange ActiveSync enables the user to reply and forward the attachment without the attachment ever being received by the mobile device. The user simply forwards the message to another user. Exchange ActiveSync knows to grab the attachment off the Exchange server and forward it to the user, and not require the mobile device to retransmit the same attachment across the network.

Additional performance-improving features of Exchange ActiveSync are the ability for a user to define peak and nonpeak times to synchronize information and the ability to change those synchronization scheduling options when roaming. By specifying peak time for sending and receiving information, a user can specify higher priority and more frequent transmission of messages. During nonpeak times, the user can specify to have large attachments sent, because message receipt and sending might not be as critical.

Another performance-improving function in Exchange 2003 is the ability for a user to mix the function of ActiveSync with Outlook Mobile Access; this is covered in more detail in the next section, "Using Outlook Mobile Access for Browser-Based Devices." Rather than sending or receiving a large attachment, an HTML Web view of the attachment can be done, enabling the user to view the attachment over a Web browser.

Improving Mobile Security

Although Exchange 2003 supports sophisticated methods for sending and receiving messages and attachments, organizations must ensure the security and integrity of the information. Exchange ActiveSync supports S/MIME encrypted attachments and 128-bit encryption on transmissions between server and client devices. With support for encryption and encrypted attachments, security of information can be improved.