Book excerpt: With a focus on connectivity, clients, and unified messaging, this book delivers the ultimate, in-depth reference to IT professionals planning and managing an Exchange Server 2013 deployment. Guided by Paul Robichaux, a Microsoft MVP and popular author, you will: Understand how Exchange Server 2013 works with previous versions Gain expert insights into supporting clients, mobile devices, and UM Take a deep dive into front-end servers; certificate and namespace management; transport rules; load balancing; client management, including Microsoft Outlook, Outlook Web App (OWA), and POP3/IMAP4; mobile devices; anti-malware and anti-spam features; Unified Messaging; Microsoft Lync; Office 365; Exchange Online.