Lync Server 2013 Mobility Technical Review

When the mobile clients were introduced in Lync 2010, a new client architecture was also introduced. Lync desktop clients communicate with Front End and Edge Servers using the SIP protocol. To provide a better user experience on mobile devices, Microsoft introduced a new communication method for mobile devices. Lync mobile clients communicate over HTTPS to send XML messages that are then translated into SIP messages on the server. This allows for a lighter-weight protocol to be used on the devices, which results in greater battery life, a seamless experience across device platforms, and the capability to maintain connection state on mobile devices. Additionally, a new server discovery mechanism was required for mobile devices. Before Lync mobile, autodiscovery of Lync services was done through DNS SRV records. However, DNS SRV records would point directly to SIP services on Lync Servers; a new method was required to direct mobile clients to the HTTPS web service for mobility. Figure 24.2 provides an overview of the architecture for Lync 2013 Mobility.

Figure 24.2. Lync Mobile architecture overview.

This section outlines the architecture and new services introduced with Lync Mobility.