Microsoft updates Exchange ActiveSync to ensure that mobile clients stay connected

Microsoft updates Exchange ActiveSync to ensure that mobile clients stay connected

The news that Microsoft is releasing a new version of the Exchange ActiveSync (EAS) protocol (16) into Office 365 might have passed you by. It certainly didn’t register on my radar, mostly because I don’t read the development blogs – I mean, how many blogs can one person follow?  Fortunately some others noticed the announcement, which is important because of the number of mobile clients that connect to Exchange via ActiveSync.

EAS 16 is now being rolled out inside Office 365 and will be included in Exchange 2016. No news exists whether EAS 16 will be backported to Exchange 2013, which currently runs Version 14.1. The move to version 16 aligns the numbering with the "wave 16" software releases that are currently in development.

Improvements are promised in three areas:

  • Enhanced calendar reliability through a reworking of the calendar workflow between server and client. This is a major benefit but ideally will be largely unnoticed by end-users. Success here will be the absence of those hard-to-diagnose calendar related problems sometimes seen when the server and client are not produced by the same company.
  • Calendar attachments. Previously calendar items synced with EAS could not include any attachments such as agendas, decks or spreadsheets. In version 16 that is now possible.
  • Syncing the drafts folder was previously not supported. We’ve added that support in version 16. Now you can start an email on your EAS device and continue editing that draft back at your desktop by retrieving the mail from the drafts folder. Or, write your draft at your computer, then make the final tweaks and send it from your phone while you're on the go.

Clients will need to be updated to use the new features. Apple has already announced that they will support EAS 16 in their iOS 9 release. I'm waiting eagerly for an update to Outlook Mobile for Windows Phone! 

Calendaring has long been the most difficult area for EAS developers to handle properly, so any improvement in this area is to be welcomed. I’m not sure whether syncing the drafts folder will be noticed by many, but I guess it is important for those who would like to do this.

The current version of EAS first appeared in Exchange 2010 SP1 to add support for user photos in the GAL and (more importantly) Information Rights Management (IRM) protection for messages. Not much has happened in the five years since, except of course a succession of client-side problems caused when other vendors attempted to do things with EAS that they should not have. Apple (as in this iOS6 example that resulted in huge transaction log growth for servers) was the most gratuitous offender, much to the discomfort of the many Microsoft employees who use iPhone and iPad devices, even at a time when the current “mobile first, cloud first” strategy was never anticipated.

Microsoft could never control how EAS licensees wrote code in their email clients to communicate with Exchange, so they have concentrated on bullet-proofing the server in the recent past so that any egregious client code can’t cause problems for Exchange. I think Microsoft has done a good job here because the chorus of concerns that used to accompany new releases of iOS and Android has calmed to a whimper.

Just over a year ago, I wrote about Microsoft’s mobile email strategy and concluded that OWA for devices was where all the attention was focused. I concluded that “EAS is now the "reach" protocol, popular with mobile device vendors because it's relatively easy to implement, it's stable, and it's well sorted” and “EAS clients will remain enormously popular and will continue to serve users well if they're content with basic email and calendaring. “

The situation was transformed last November when Microsoft bought Acompli and then relaunched their Apple and Android clients in a bumpy rebranding exercise in January 2015. In short order, the OWA for Android project, which had never really gotten anywhere, was dropped and the OWA for iOS client began to shed functionality like support for Office 365 Groups, meaning that no Microsoft mobile client will support this feature until the new Groups app promised at Ignite is launched in the “near future”.

What’s clear now is that Microsoft’s premier mobile email clients are the Outlook duo, accompanying by a somewhat bewildering array of other mobile clients designed to access different parts of the Microsoft Office ecosystem, such as the Delve client, Groups client, and so on. Given the propensity of mobile clients to update, we’ll soon be in an update frenzy to keep all the clients patched. Speaking of which, I should acknowledge the June 10 announcement that the Outlook clients now support OAuth, Active Directory Authentication Library (ADAL), and multi-factor authentication against Office 365 accounts. According to a tweet from Outlook boss Javier Soltero last night, a future version of Exchange will support these authentication methods for on-premises deployments. I assume this means Exchange 2016.

The Outlook clients, which use ActiveSync in their own particular way to communicate with Exchange, are a good example of software that follows a fast development cycle. The progress that the Outlook team has made to address corporate perceptions of their shortcomings (especially in the security space) since their launch at the end of January is pretty impressive,

In any case, the question is whether a role still exists for EAS and the answer is emphatically “yes”. Major vendors like Apple are no doubt pleased that Microsoft has done a fine job of supporting their app store, but they would be less than happy if Microsoft dropped EAS and forced Apple to support a new protocol to connect the iOS email client to Exchange. The same is true for the multitudinous Android vendors, each of whom has their own take on what a perfect email client should behave.

Microsoft’s mobile email strategy has shifted dramatically in the last year, but its unsung hero plods along to enable connectivity for the masses. The article that introduces EAS 16 recommends that developers review the Outlook REST-based APIs and consider them for future development because these APIs incur no licensing fees and “are great for both mobile device-to-Office 365/Exchange Online, and service-to-Office 365/Exchange Online applications.”

All of which is true, but it does kind of leave the on-premises market out of the debate, which is something that EAS would never do.

Follow Tony @12Knocksinna

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