By Carl Klatsky, Comcast; DeFu Li, Comcast; Jason Combs, Comcast; Anton Grichina, Harmonic; Adam Levy, Harmonic
The Virtual Cable Modem Termination System (VCMTS) and Virtual Services Gateway (VSG) are newer network elements that have quickly become vital to running a large MSO network. The VCMTS disaggregates the traditional Cable Modem Termination System (CMTS) functions across a generalized computing structure. The VSG is in the logical path of the customer data packets enabling usage and quality analysis use cases. The next step is to integrate these two virtualized network elements. The authors will outline an approach to building a hyper scale VSG that can scale in proportion to future needs. This approach uses a Smart Network Interface Card (NIC) with programmable network function accelerators for the platform’s physical connectivity along with a control plane that utilizes the Linux SwitchDev model and Linux Traffic Control (TC) flows to direct traffic between the VCMTS and VSG systems. The approach allows both elements to rapidly scale up by simply increasing the capacity of the switching fabric and adding more compute nodes.