ClearOne StreamNet Integration - Manual (Page 11)

Chapter 2: Controlling A StreamNet System 5
STREAmNET CONCEPTS
There are few concepts that must be understood to properly understand StreamNet.
Services
A StreamNet service is an abstraction. It is a functional software module but it can be thought of as a virtual
device. A service performs a single function such as capturing analog audio and streaming that audio onto
the network. Another service may perform the function of converting the network audio stream to analog and
amplifying it. Still another service may provide an interface to a third party lighting system. A single physical
device may support many services of various types.
The service concept greatly simplifies controlling the StreamNet system. For example, control messages can
be addressed to the name of an AV zone (a service) instead of to “Device 1 at IP address, 10.15.65.113, output
number 7”. The controller does not need to know which physical device is providing the function or what the
physical configuration of that device is – just the service name. The control messages are simply addressed
to “Zone 1” and StreamNet ensures the correct AV zone reacts. Details about the types of services and the
functions performed are described in later sections of this document.
STREAmNET ADDRESSING
StreamNet ASCII messages may be sent, using any of various unicast methods, which include UDP (Unicast)
and TCP, to any StreamNet device. If addressed correctly, the message will be routed to the desired service(s).
Also, the messages may be sent to the StreamNet System multicast address. In this case, all StreamNet
devices receive the message simultaneously, but only the addressed services accept the message and react
to it. Messages may be addressed to a Service, a Group or a Room.
It is not necessary to know the IP addresses of the individual StreamNet devices to communicate with them. All
messages are addressed to service names associated with the devices during the configuration process.
If the 3rd Party Controller or software has the ability to send Multicast UDP messages, then all ASCII messages
may be sent to the default system Multicast Address and the destination device or group of destination devices
will receive it. Responses and status may be received by unicast/multicast UDP. If the 3rd Party Controller or
software does not have multicast capability, the messages may be sent Unicast UDP to any StreamNet device
and it will be forwarded.
If the 3rd Party Controller is also listening to its own (i.e., different) multicast address for responses, the
controller and the StreamNet system do not have to be in the same subnet.
The StreamNet system multicast address should not be used for responses. 3rd Party Controllers should
subscribe to use a separate unicast address or an unused multicast address to receive responses (see the
section on
Subscription below).
Unsolicited status messages may be received by the 3rd Party Controller.
Group Addresses
Services can be members of named “groups”. A group address, or “group name”, is just a way of addressing
multiple services simultaneously with a single control message. A service may be a permanent member of a
particular group or it may join and/or leave the group. There may be special group names which are used for
specific purposes; for example, the group name “ALL” includes all services in the StreamNet system.