Explanation of Exchange ActiveSync Push Functionality in SmarterMail
Microsoft Exchange ActiveSync (EAS) is available as an optional add-on to a SmarterMail Enterprise license. EAS uses direct push technology to sync email, calendars, and contacts, as well as tasks, notes and folders on those supported devices, in real time to smartphones, tablets, and Outlook 2013. Below is an explanation of the EAS push functionality when used with SmarterMail.
SmarterMail follows Microsoft's documentation on how the Ping command must be implemented. You can read more about this from Microsoft's documentation on Monitoring Folders for New Items.
The important section in the document to note is the following:
The server SHOULD delay sending a response until either of the following conditions are met:
The interval specified by the HeartbeatInterval element has elapsed.
An item is added to one or more of enumerated collections. This condition includes new mail being delivered and items being copied or moved into the collection.
The server SHOULD NOT send the response before the interval specified by the HeartbeatInterval element for any other changes to a collection, including items being modified, items being deleted, or items being moved out of the collection.
Simply stated, EAS will push changes to your mailbox when the above scenario is met, such as when a new email is delivered to the mailbox, items are marked for deletion or were moved within the web interface, etc. This is the best way to implement ActiveSync as this reduces high CPU, memory and bandwidth issues that can occur when continually syncing mailbox data.
NOTE: If syncing issues and delays are seen on mobile devices and tablets, such as an iPhone, iPad, Galaxy Note, Nokia Windows phone, or in a desktop client like Outlook 2013, it is likely caused by the device/client delaying the command to SmarterMail. For this reason, some changes may not be automatically reflected in SmarterMail. In these cases, the delay is not directly related to SmarterMail but is a limitation of the device/client itself.