Exchange ActiveSync (EAS)

Best-in-class, real-time syncing of email, contacts, calendars, and tasks on mobile and tablet.

In the mobile era, consumer and business devices respond immediately to users’ gestures, their requests, and even their voices. Users expect that key communications and productivity applications will be just as responsive, keeping them up-to-date and organized in real time.

Microsoft’s Exchange ActiveSync (EAS) is a powerful communications protocol that enables the syncing of email, calendars, contacts, and tasks on tablets and mobile phones, pushing accurate, reliable data. Original Equipment Manufacturers (OEMs) and other companies license Exchange ActiveSync from Microsoft.

Many OEMs license the protocol as part of a broader suite of Microsoft licensing solutions, which helps them create more powerful mobile phones and tablets, wearable devices, connected cars, and other software, as well as enabling users to access critical information from anywhere.

How Exchange ActiveSync Works

The Exchange ActiveSync protocol is the language spoken between a mobile device or tablet and a messaging server, enabling synchronization of pre-defined objects. The EAS protocol allows devices to synchronize email, calendar, contacts, and tasks over the air with Microsoft Exchange, Outlook.com and other servers which implement the protocol.

Syncing is the process of reconciling differences between data stored on a device and on the Exchange Server. A mobile device or tablet will have its own email, contacts, calendar and task applications, maintaining its own collection of objects and changes made since its last sync with the Exchange Server.

The device may initiate a new sync by sending a set of updates to the Exchange Server and requesting the Exchange Server respond with its own updates. The Exchange Server processes updates it receives, resolves any conflicts, and sends its changes back to the mobile device.

EAS is the solution used on Windows Phone-based devices to ensure accurate, up-to-date syncing. OEMs, application developers and service providers can license Exchange ActiveSync for use on their own devices, software, or servers.

Benefits of EAS

Broadly Licensed Protocol

Over 100 OEMs, developers and software companies have licensed EAS. Many of the world’s most widely-used email clients adopt EAS to sync email and other data with top messaging servers.

EAS Implementation

The Exchange ActiveSync Overview and Exchange Server Protocol Documents offer additional information about Microsoft’s implementation of EAS.

Learn More About EAS

Contact us to learn more about how EAS can improve your next mobile device or tablet.