This list highlights the vendors that support native registration to a Lync server:
• Polycom DMA—The Polycom DMA provides a connection point for standards-based video endpoints and flexible routing rules.
• Cisco VCS—Cisco VCS is a very similar product to the Polycom DMA and also provides standards-based integration and registration among H.323, SIP, and ISDN systems.
• Radvision SCOPIA Video Gateway—The Radvision product provides signaling integration between Lync endpoints and their H.323 gatekeeper product. It does not provide registration for H.323 devices by itself like a Polycom DMA or Cisco VCS, but it does double as a media transcoding device.