Polycom SR12 Speaker System User Manual


 
Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12
8 - 6
The command responses are received back and include the mute status for all
virtual channels in the “Mics” virtual channel group.
When there are multiple simultaneous control sessions to a SoundStructure
system, the control session that sends commands will also receive command
acknowledgements for all of its commands. Other control sessions will only
receive command acknowledgements from a command entered from another
control session if a parameter value changes.
For example, if a control session queries the value of the mute status, only that
control session will receive the acknowledgement of the mute value. However
if the control session changes the mute state, for example, all control sessions
will receive an acknowledgement.
SoundStructure Device Discovery
SoundStructure Studio uses a discovery mechanism for identifying Sound-
Structure devices on the network. SoundStructure Studio sends a UDP
discovery broadcast using port 52774 and all SoundStructure systems that
receive the broadcast will respond and identify themselves.
If the IP address changes on the SoundStructure device, such as if the dynamic
IP address lease expires and a new IP address is received, it may take up to 75
seconds for the discovery mechanism to restart.
This discovery mechanism only creates network traffic when SoundStructure
Studio is discovering devices caused by the user opening the Connect to
Devices window.
Because both the discovery and command channels use port 52774, traversing
firewalls only requires opening port 52774 for both UDP (for discovery) and
TCP (for commands) to allow for remote access of the SoundStructure device.
Control sessions receive acknowledgements for commands entered in that session
and only receive command acknowledgments from other command sessions if the
other command sessions change the value of a parameter.