Office 365 is a cloud service. Characteristic for cloud services is that they are offered on a large scale. Microsoft offers Office 365 for Europe from its data centers in Amsterdam and Dublin. These data centers contain hundreds of thousands of servers that serve just as many customers. From these servers, Microsoft offers highly standardized services. This standardization brings many advantages, but certainly also disadvantages with SharePoint development.
(1) Office 365 products are not customizable
Microsoft offers several products as a service in Office 365. These are Office 365 ProPlus, Exchange Online, SharePoint Online and Lync Online. Microsoft controls the way the software is installed and offered to its customers. Customers have the option to configure the software to their own liking. However, it is impossible to programmatically adjust the software. After all, the servers in the cloud are shared by many customers. The simple installation of all kinds of components is therefore not supported.
In order to still offer companies the opportunity to expand the functionality of Office 365, it is possible to provide all kinds of additional extensions with a new App model and via web services. Organizations can do this themselves, but they can also purchase these extensions from suppliers or via the Office App store. Installing software on the Office 365 servers, however, remains impossible.
Many software vendors have now adapted their solutions so that they can work with Office 365. So most components are available, but not everything. So check whether any plugins purchased for the Office server products are actually suitable for Office 365 or look for other suppliers that offer similar functionality.
(2) The Office 365 services have hard limits
Microsoft has done its best to make the service as generic as possible. She pushes the boundaries. Mailboxes, for example, have a standard size of 25GB. A size that most business email users dream of. Other examples of these hard ‘limits’ are the maximum file size in SharePoint Online and storage capacity of SkyDrive Pro. These are respectively a maximum of 250MB per file and 7GB in total.
The boundaries of the Office 365 services are accurately described in the so-called Service Descriptions. Although the limits are usually so high that the vast majority of organizations are not affected by this, in specific cases there will be a situation in which the limits are not high enough. If no alternative solution can be found in the form of, for example, an internal policy adjustment, it is therefore better not to opt for Office 365.
(3) ‘Only 99.9% availability’
According to the contracts, the Office 365 service may be down for a maximum of 44 minutes or 0.1% per month. Many companies do not manage this by themselves. The internal automation cannot achieve an uptime of 99.9% of its own services and may be much lower. However, sometimes 99.9% is not good enough. In situations where documents on SharePoint, for example, are vital, e-mails must always be handled within a set number of minutes or Lync conversations must never be interrupted, Office 365 (or any cloud service at all) cannot be chosen. At least not for the services or users who demand 100% uptime.
(4) Dependence on the Internet
Many organizations cannot function without an internet connection. E-mail has become an integral part of the daily process. However, it is possible that no internet connections are available. Examples of this are organizations that often operate in third world countries. The internet connections in such countries are not always fast or stable. In such environments, files are better stored locally than in the cloud. After all, the unpredictability of the internet does not always guarantee that the files are always available.
Microsoft has paid a lot of attention to making information in Office 365 available offline, even in the event of a lack of internet connections. For example, the Outlook Web Access client is available offline, the emails in Outlook are available offline and all files can be saved offline with the new SharePoint Sync option. In situations where only a slow or unstable internet connection is available, it must be determined whether this is sufficient.