Today most people own a tablet or smartphone and are happy to bring their virtual personal assistant to work. People want the flexibility offered by their smart devices in their business applications too. Sooner or later, they will ask if they can access the company's resources using their own device, so it is best to have a BYOD (bring your own device) policy in place.
If you can gain administrative control over the device, for example by using Mobile Device Management (MDM), you can grant this access in a secure manner. But many people won't want you to limit the way they use their expensive smartphones.
You can, however, allow these devices on your network in a restricted way. By using identity-based access control, SpotIT is able to provide granular network access. For example, a company employee using a registered personal device might only be allowed to perform mail synchronization and access the Internet, while all traffic is checked for security risks.