ND SatCom SKYWAN IDU 7000, Manual

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2010-10-26 Network Design and Engineering Guide 25
General Carrier Design
Essential SkyWAN
®
Satellite Link Layer Features
2.3.2 Master and Slave Functionality
In a traditional star network the hub station acts as both, a traffic hub and a network manage-
ment station. In a fully meshed
Sky WAN
®
network, the traffic hub functionality is not necessary
since all stations can reach their peers directly over the satellite link.
The network management functionality however is always necessary and is normally provided
by the
Sky WAN
®
master station. A master station must fulfil the following fundamental require-
ments:
-
Indoor Unit requirement: The master station must be a Sky WAN
®
IDU 7000 equipped with
a frame plan generator (FPG) board.
- Satellite link requirement: The master station must be able to reach each other station in
the network over a satellite link with sufficient quality. In a star or hybrid network this means
that only peer or hub stations may perform the master role.
RDR license is required for a master station.
Control Communication: Reference and Request Bursts
The following figure 2-6 presents an overview of the control tasks performed by the master sta-
tion:
Figure 2-6 Master - Slave Communication
The control communicaton between master and slave stations is based on specific signal
types:
- Reference Burst: from Master to Slaves.
- Ranging and Request Bursts: from Slaves to Master.
The master station uses reference bursts to transmit the frame plan which specifies the trans-
mission times for every station in the network. Additional information is distributed with these
bursts:
-
Slave station authentication.