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If the temperature exceeds 57.5 °C (137 °F), the GRF does an automatic system shutdown.
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For the GRF 16S model, the cooling fan can be replaced while the GRF is in operation.
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There are two types of adapters on the GRF: the media adapters and the IP Switch Control Board.
The media adapters are independent of each other and can be replaced or removed without affecting any other adapter or the operation of the GRF.
However, the IP Switch Control Board is critical to the GRF. Should this board be unavailable, the router fails.
•Crosspoint switch
The crosspoint switch is a 16x16 (16Gb per second) or 4x4 (4Gb per second) crossbar switch for the GRF 16S and GRF 04S, respectively, see Figure 12 on page 27. It is the I/O path used when the media adapters need to communicate with each other.
Serial Interface
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CPU
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Combus
80 Mb/s bus | User Interface | |
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Dynamic Routing Engine (Route Manager)
Configuration/Control
16MB Rx / 16MB Tx Buffers
Speed decoupling
WAN delays
QBRT Route Table Lookup
Times range from
IP Header
Route decisions
4 Gb/s Switch