FortiGate-7040E fast path architecture

The FortiGate-7040E chassis schematic below shows the communication channels between chassis components including the management module (MGMT), the FIM modules (called FIM1 and FIM2) and the FPM modules (FPM3 and FPM4).

The management module (MGMT, with Intelligent Platform Management Bus (IPMB) address 0x20) communicates with all modules in the chassis over the base backplane. Each module, including the management module, includes a Shelf Management Controller (SMC). These SMCs support IPMB communication between the management module and the FIM and FPM modules for storing and sharing sensor data that the management module uses to control chassis cooling and power distribution. The base backplane also supports serial communications to allow console access from the management module to all modules, and 1Gbps Ethernet communication for management and heartbeat communication between modules.

FIM1 and FIM2 (IPMB addresses 0x82 and 0x84) are the FIM modules in slots 1 and 2. The interfaces of these modules connect the chassis to data networks and can be used for Ethernet management access to chassis components. The FIM modules include DP2 processors that distribute sessions over the Integrated Switch Fabric (ISF) to the NP6 processors in the FPM modules. Data sessions are communicated to the FPM modules over the 80Gbps chassis fabric backplane.

FPM3 and FPM4 (IPMB addresses 0x86 and 0x88) are the FPM processor modules in slots 3 and 4. These worker modules process sessions distributed to them by the FIM modules. FPM modules include NP6 processors to offload sessions from the FPM CPU and CP9 processors that accelerate content processing.