[[TOC(Documentation/Topology/*)]]

= Topology Control in SB4 =

As shown in Figure 1, sandbox 4 consists of 8 nodes and a WiMAX subsystem that consists of a basestation and a controller. To prevent interference, each node is housed in [http://www.ramseytest.com/ Ramsey Electronics RF enclosure] that provides 80 dB of isolation. Nodal wireless devices (Atheros 5000X mini-PCI card and Intel 6250 mini-PCIe 802.11/802.16) are connected to a power combiner and fed through the enclosure access port to the outside SMA connector which is wired to a single input/output of the ports of the [wiki:Documnetation/Topology/aRFControl RF Transceiver Test System] from [http://www.jfwindustries.com JFW Industries]. This configuration enables fairly tight control of RF attenuation between the nodes. The topology is controlled through the [http://omf.mytestbed.net OMF] based [wiki:Documentation/Services/bInstrumentationControlService Instrumentation AM].

[[Image(SB4.jpg, 600px, link=, align=center)]]

Basestation is controlled through  [http://omf.mytestbed.net OMF] based [http://wimax.orbit-lab.org/wiki/WiMAX/17#a9.WiMAXRFAggregateManagerService WiMAX RF Aggregate Manager Service] that is running on machine cons-wm-01.

Example of topology control (execute on console.sb4):

To set attenuation between node1-8 and the BS to 20 dB
{{{
    wget http://internal2.orbit-lab.org:5052/instr/set?portA=8&portB=9&att=20
}}}

Example of wimax control (execute on console.sb4):

To turn ARQ on ([http://wimax.orbit-lab.org/wiki/WiMAX/17/01arq#arq-ARQControl ARQ Control] part of wimaxrf AM) 
{{{
    wget http://cons-wm-01:5052/wimaxrf/arq?enable=true
}}}