With Lync Server 2013, the integrations with Exchange that existed in previous versions will continue to be featured, and several additional integrations are introduced as well. Lync 2013 integrations for Exchange include the following:
• Unified contact store (new)
• Lync archiving integration (new)
• High-resolution photo storage (new)
• Outlook Web App integration
• Unified Messaging voice mail integration
The new Exchange integration features previously listed require both Lync 2013 and Exchange 2013. Therefore, an organization must upgrade both products to the newest versions in order to take advantage of all the Exchange integration features built into Lync 2013.