Mimecast Whitepaper: SaaS- Threat mitigation from the cloud
You can’t treat security as a set of isolated point systems. That’s true of your business information in general and of your email architecture specifically. Protecting information is one side of the coin; making it available and accessible is the other and if you do both right you can improve productivity as well as avoid risk.
The cloud isn't just the most effective place to secure email, before any threats or intruders ever reach your network; it’s also the most efficient. Cloud-based email services can offer full protection with the promise of availability and reliability too.