Media Bypass

The fact that the Mediation server role can now be collocated on a Front End Server significantly eases the infrastructure requirements for implementing Lync Server voice. The other big advancement is the capability for media bypass from Lync endpoints.

When possible, a Lync client will use the G.711 codec to communicate directly with an IP PBX or media gateway that eliminates the need for the Mediation server to be involved with converting between G.711 and RTAudio. This change should help reduce the number of hops, remove potential latency, and improve the overall voice quality. As shown in Figure 17.16, the SIP signaling information still flows through the Mediation server role, but the Lync endpoints can send their media directly to the IP PBX or media gateway.

Figure 17.16 Media Bypass