Pushing Network Programmability to the limits with SRv6 uSIDs and P4

Abstract

P4 is a domain-specific programming language for expressing how packets are processed by network devices. P4 is used to program P4-enabled devices with a custom forwarding pipeline. SRv6 is a network architecture that encodes a list of instructions in the IPv6 packet header to define a network-wide packet processing program. Each instruction defines a node to process the packet and the behavior to be applied to that packet by that node. Recently, the SRv6 architecture has been extended to support a set of new instructions, known as uSID instructions, that provide a better scalability and MTU efficiency. In this demo paper, we provide a P4 forwarding pipeline that supports the SRv6 uSID instructions. Our implementation leverages the P4 BMV2 behavioral model and extends the ONOS controller to support the new SRv6 behaviors. Finally, we show two scenarios where we use our implementation to provide a fully programmable network fabric.