Containers, by design, are like digital islands—self-contained units bundled with everything they need to run independently, from application code to dependencies and runtime. This autonomy delivers significant security and deployment advantages, but it also creates challenges—especially in networking. Isolated by default, containers must be carefully connected to allow distributed applications to function cohesively. As Bill Mulligan of Isovalent puts it, “In the world of distributed computing, everything goes over the network, making it the critical component for applications to work and work together.”
Historically, bridging these containerized environments meant leaning heavily on complex virtual networks—layers of software-defined switches, adapters, firewalls, and proxies. While these tools helped containers communicate, they also introduced inefficiencies and operational complexity. Rather than continuing to abstract upward from physical infrastructure, the solution to container networking may lie in going deeper—into the operating system kernel itself.
Enter eBPF (extended Berkeley Packet Filter), a powerful Linux kernel technology that allows developers to run custom, sandboxed programs directly within the OS. This deeper integration enables high-performance, secure, and programmable networking without the need to modify application code or reconfigure the network. As Taranvir Singh from IDC explains, eBPF eliminates the reliance on sidecar proxies and iptables by moving traffic processing and policy enforcement directly into the kernel—bringing both resource efficiency and fine-grained control to the forefront.
Before eBPF, container networking was often seen as opaque and operationally brittle. Legacy techniques like iptables became increasingly unwieldy at scale, and the duplication of network stacks across containers led to unnecessary latency. “With eBPF, we can bypass parts of these superfluous networking stacks,” says Liz Rice of Isovalent, highlighting the technology’s ability to streamline traffic flows without sacrificing security or observability. In short, eBPF isn’t just improving container networking—it’s transforming it from a bottleneck into a core enabler of cloud-native scalability and performance.