Specifications

IP Networking
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Figure 18: Hierarchical Network
Further details on setting up a cluster can be found in the “3300 ICP Multi-Node Management
Clustering” document under the 3300 product documentation on Mitel-on-Line.
Call Handling, Routing, and Bandwidth
A call consists of two parts: signalling and voice streaming.
Using TDM, typically over the PSTN, the two parts of the call follow the same path and are
closely linked in their routing. In a tandem connection from site A to site C, via tandem site B,
voice is handled by the TDM switch at site B. In effect, the tandem TDM switch reroutes the
voice part of the call and establishes a second signalling path. It is involved in both voice and
signalling connections.
Using IP, voice can stream directly between endpoints (usually), but signalling still travels via
the tandem unit. Thus, in a tandem connection, voice streams directly from A to C, while
signalling goes from A to B and then B to C.