Cloud Services don’t go down do they?
I am sure they are not sold that way, in fact, many tout 99% up time. But cloud services are no more special than your internal infrastructure and they are subject to the same outages as any network. The likes of AWS (Amazon Web Services), Google Apps and Microsoft Online Services essentially use the same technology as most organizations, albeit with a lot more redundancy than the average Enterprise Network.
Of course there are service credits that you can apply for if there is an outage, but those credits often only equal 10% of your monthly fee.
Of the 720 hours available in a month, a 99% up time equates to an 8 Hour outage. Can you afford an 8 hour outage? Does the 10% cover the losses of your full work day outage?
This is not to say that you are not subject to the same outage with an internally hosted infrastructure. In some respects you have more control over your own infrastructure and if built with redundancy in mind, you can almost eliminate downtime, barring any physical disasters.
I am not necessarily advocating internal infrastructure over Cloud Services, in fact we both use and provide Cloud Services at End to End, but I do want to educate everyone on the pros and cons of each.
Maintaining your own infrastructure can be expensive and time consuming and if IT isn’t your forte, cloud services make a lot of sense.
You must have some faith in your cloud provider, faith that when, not if, there is downtime it will be minimal. Then it is your job to create enough redundancy in your own network to ensure you are always able to get to the cloud. At a minimum I would recommend two Firewalls in an Active/Passive cluster, with two small out side switches and two Service Providers, using two separate mediums (Ethernet and Wireless). Even this is not full proof, but will ensure that any number of hardware and circuit failures will still have you connected to the cloud.
If you are still unsure whether you are ready to embrace the cloud, have a close look at all of your applications, you may already be using the cloud.