Office 365: why it scores over on-premise software

David Cartwright Advice
13 Nov, 2012

Implementing Office 365 is a sensible way forward for SMBs: it saves a lot of hassle

It's no surprise that Microsoft is making a huge push to sign SMBs and enterprises up to the Office 365 service. Cloud computing is, as we all know, a major facet of Microsoft's desired future; while generic server and storage provision forms a major part of the service offering, the company now wants its customers to branch into the cloud for its applications too.

Office 365: a brief introduction
Office 365 is, basically, a collection of Microsoft applications hosted in the cloud. The company refers to it, pretty accurately actually, as “the online companion to Office”; the six building blocks it comprises are hosted email, hosted calendars, web conferencing, web versions of Office applications, file sharing and corporate websites.

The facilities you get depend on the plan you pay for. At the basic level is the hosted email service for $48 per annum per user. The “small business” plan labelled P1 adds, for another $24 per annum, instant messaging and VC, plus file sharing, website hosting and viewing (but not editing) of Office documents.

Going up a notch, plan E1, at $96pa, is the starting point for enterprises, as it gives 24x7 technical phone support, SharePoint and Active Directory synchronisation. Finally plan E3, at $240pa per user, adds voicemail, email archiving and unlimited storage, and full Office apps. P1 is the only plan that has a user limit; the ceiling of 50 users sits it firmly in the small business realm.

Office 365 is managed via a web portal which is, it has to be said, extremely comprehensible and straightforward to use. In fact the only tricky aspects of using Office 365 come in the enterprise-level offerings when you have to deal with the integration between your internal systems and the Office 365 cloud. The main aspects you need to deal with are DNS, firewalls and directory synchronisation.

Office 365 is managed via a web portal which is extremely comprehensible and straightforward to use

DNS is required if you're going to be using the Lync messaging and VC service. Although all you're really doing is adding some SRV (service) records, this can be something of a faff if your DNS is hosted by a third party and database management is done through a portal because SRV record management can often clunky and takes a bit of working around.

Directory Synchronisation is achieved using Active Directory Federation Services (ADFS), which means you'll need Windows Server 2003 R2 or later. What you're basically doing is providing the cloud service with a read-only copy of the pertinent aspects of your Active Directory structure in order that your internal users can authenticate against the cloud servers.

The firewall aspect's pretty obvious: any sensible organisation won't, by default, have rules permitting arbitrary access to the Office 365 servers on the required ports. There's nothing difficult about this, though – just look up the current port list on Microsoft's Web site and implement it on your firewall. One quick caveat: as hosting services change, your firewall rules need to keep up and you won't be actively notified by Microsoft when this happens, so keep an eye on their support portal to make sure you keep up.

Neither of these steps is particularly onerous, though, and you'll soon be connecting to the Office 365 services without really thinking about it.

Office 365 versus on-premise
To understand whether you should be going for an on-premise offering or a cloud offering, we'll look at each of the components and discuss how well (or otherwise) it's suited to cloud operation.

Web site hosting

Let's be honest: you probably don't really give a stuff about website hosting. Perhaps there's a small chance that you might want to drive a part of your site using Active Directory for user logins, but there will be few organisations that consider this feature as a clinching factor for signing up to Office 365.

We mentioned earlier that Office 365 is termed “the online companion to Office”, and it's in the web applications that htis applies most. The message is clear: you're not going to use the cloud-based version of the basic Office apps (Word, Excel, etc) in place of the desktop versions – they're there as a supplement to them. So the cloud version integrates nicely with the desktop version, and being a hosted offering you have the obvious bonus of being able to share docs with colleagues and work on them via the web wherever you are. The vast majority of organisations will, however, be perfectly content with the desktop-based applications and will use the web alternatives sparingly, if at all.

File sharing