Polycom RMX 1500 Administrator's Manual page 972

Polycom RMX 1500/2000/4000 Getting Started Guide
Interactive Connectivity Establishment (ICE)
H-4
Interactive Connectivity Establishment (ICE) provides a structure/
protocol to unify the various NAT Traversal techniques that are used to
cross firewalls.
It enables SIP based endpoints to connect while traversing a variety of
firewalls that may exist between the calling endpoint (local) and the MCU
or called endpoint (remote). It is the only way for remote Microsoft Office
Communicator/Lync users to call into the enterprise without a VPN.
ICE Guidelines
• ICE is available in MPM+ Card Configuration Mode (Version 7.0 and
later) and MPMx Card Configuration Mode (Version 7.1 and
• RMX ICE implementation complies with Microsoft ICE
implementation.
• ICE is available only in IPv4 environment.
• ICE can be implemented in an environment that includes a STUN
server and a Relay server (for example, Microsoft AV Edge server).
• The firewall must be UDP enabled.
• The RMX must have a unique account in the Active Directory and
must be registered with the Office Communications/Lync server.
• ICE is supported only within a single IP Network Service per RMX
and not in Multiple Networks configuration.
• Ensure that the RMX system SIP signaling domain has been allowed
on the Lync Server edge server to which you are federating (if your
deployment does not include a DMA system).
later).