Published on 7 July 2011
SaaS (Software as a Service) is a truly wonderful thing for SMB's: no nasty server rooms, no nasty maintenance, no nasty application support and upgrading - sounds like the complete panacea and in many ways it is. But, you're completely at the mercy of the network, and in this case, it's public networks.
Forget the 'my network is down so I can't use my app' issue, that's obvious and easily tackled by means such as multiple ADSL's. Or, even, I'll work from home! That's the beauty of the SaaS cloud, use it anywhere you like. The risk may stand with your software vendor.
You should be concerned about service availability from your SaaS provider, but fear not: they will provide you with an SLA (Service Level Agreement) with guarantees to defend against that. Unfortunately poor network performance is invidious and if the app is still working no SLA is broken.
So, no SLA was broken by either your ISP (Internet Service Provider) or your SaaS provider. You were told by your ISP that the numbers you were given at time of sign up for bandwidth were the maximum expected and they warned you that there would be contention. Which in practice means you may only get a trickle of the advertised bandwidth. Will your SaaS applications work then? What do you do?
When choosing your SaaS applications, don't just ask about the 99.9% availability, ask about:
If you are planning to use your application over wireless networks like 3G and GPRS this matters even more, because here, bandwidth can be very scarce with data loss and latency high.
There are tools available to predict the behavior of applications in these 'difficult' network conditions. While we are not suggesting that you all individually try out your proposed SaaS app with these tools the SaaS provider should have done this - ask about their results.
With ADSL, for example, you were told by your ISP there would be contention, so this is to be expected, what you'd really like to know from your SaaS provider is that the application is not network hungry and so can survive on the relatively small amounts of bandwidth that is available, especially if you try to use the app from a mobile device or a PC with a mobile internet dongle.
Bear in mind your SaaS app trial can be misleading in performance terms. When you did a trial your network conditions may have been very good, the numbers of users small compared to the final number of users for that app. Without knowledge of things like bandwidth per user and other network conditions you may be deluded about how well the app will work when used in production.
Summarizing the whole thing SaaS is wonderful but you are highly dependent on the network and not just network availability. Make sure to ask your vendor how well they perform, ask for proofs and don't let them shut down your business!