The security built into Lync and what to configure

Office 365 has security built in from the ground up. The physical and logical security built into the datacenter is phenomenal. This security is further enhanced with the in-built safeguards within SharePoint and Exchange, together with the extra protection provided by Microsoft Forefront online protection. However the security components don't stop there. There is administrator security and user controlled security for all components in office 365, not to mention remote wipe for mobile phones. So what security is required for Lync communication and what security is built into Lync?