This article from gigaom provides some good suggestions on how to lock down a cloud from cyber attacks. We have translated their suggestions into the Top Five Questions to Ask Your Cloud Provider (before signing up). We have also provided the answer you should expect to hear.
A: We store your data in multiple, secure data centers across the country.
2. Q: How do you protect our data?
A: We protect your data in transmission and data at rest through encryption. Our multifactor authentication will stop unauthorized users from breaking in via the username/password channel.
3. Q: Do you scramble passwords?
A: We scramble passwords, blocking wannabe cross-site request forgers and scripters.
4. Q: Do you offer good detection and logging?
A: We log all unsuccessful login attempts. We retain log files and analyze them in real time. We also give your IT team administrative controls so that they can proactively prevent unauthorized activity in the cloud.
5. Q: What is your process for handling intrusion(s), hack(s), and/or security breach(es)?
Remember, the above is a good starting point for selecting a secure cloud provider, but don't skimp on security when selecting a provider. Be sure they give your IT team some insight into how the system is operating.