The SDN Policy Offload pipeline is a bump-in-the-wire (BITW) implementation ideal for a SmartSwitch or an appliance form factor as shown in Figure 1. When deployed inside a SmartSwitch as a top-of-rack device or in an appliance, the DPU is not visible externally because it is integrated into the device providing network service acceleration to any traffic ingressing and egressing the device. When the DPU is deployed in an appliance for service aggregation in the data center or a colocation facility, it connects to the network devices and performs network and security services for various workloads and network traffic with the help of traffic redirection to the service appliance.
The DPU connects to a switching ASIC as a BITW to control packets to and from the wire and send it back to the switching ASIC forwarded to its next hop or destination. A single DPU can provide multiple networking services in parallel, but also multiple DPUs can be connected to scale out performance or achieve high availability. The BITW approach includes an appliance mode using an x86 system with DPUs deployed in the PCIe® slots.
The SDN Policy Offload pipeline can be easily enhanced to support a host-to-network deployment with additional services, as shown in Figure 2.