Cilium: Programmable Linux Networking with Dan Wendlant and Thomas Graf

Cilium is open-source software built to provide improved networking and security controls for Linux systems operating in containerized environments along with technologies like Kubernetes. In a containerized environment, traditional Layer 3 and Layer 4 networking and security controls based on IP addresses and ports, like firewalls, can be difficult to operate at scale because of the volatility of the system. Cilium is eBPF, which is an in-kernel virtual machine which attaches applications directly to code paths in the kernel. In effect, this makes the Linux kernel “programmable” without changing kernel source code or loading modules. Cilium takes advantage of this functionality to insert networking and security functions at the kernel level rather than in traditional Layer 3 or Layer 4 controls. This allows Cilium to combine metadata from Layer 3 and Layer 4 with application-layer metadata such as HTTP method and header values in order to establish rules and provide visibility based on service, pod, or container identity. 

Isovalent, co-founded by the creator of Cilium, maintains the Cilium Open Source Project and also offers Cilium Enterprise, which is a suite of tools helping organizations adopt Cilium and overcome the hurdles of building a secure, stable cloud-native application. 

Dan Wendlant and Thomas Graf are the co-founders of Isovalent. Thomas, the firm’s CTO, was the original creator of the Cilium open-source project and spent 15 years working on the Linux kernel prior to founding Isovalent. Dan, Isovalent’s CEO, has also worked at VMWare and Nicira. They join the show today to talk about why Cilium and Cilium Enterprise are a great choice for organizations looking to build cloud-native applications.

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