Juniper SRX5600, Hardware Manual

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SRX5400 and SRX5600 Services Gateways have one SCB each installed and you can install a second SCB
for redundancy. The SRX5800 Services Gateway has two SCBs installed and you can install a third SCB
for switch fabric redundancy.
The host subsystem is composed of a Routing Engine installed directly into a slot on the faceplate of the
SCB. When there is no Routing Engine is a SCB, its slot must be covered with a blank panel.
Figure 25: Switch Control Board SRX5K-SCB
Each SCB consists of the following components:
•
Chassis management Ethernet switch.
•
I2C bus logic, used for low-level communication with each component.
•
Component redundancy circuitry.
•
Gigabit Ethernet switch that is connected to the embedded CPU complex on all components.
•
Switch fabric—Provides the switching functions for the IOCs.
•
Control FPGA—Provides the Peripheral Component Interconnect (PCI) interface to the Routing Engine.
•
1000Base-T Ethernet controller—Provides a 1-Gbps Ethernet link between the Routing Engines.
•
Ethernet switch—Provides 1-Gbps link speeds between the Routing Engine and the IOCs.
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