Cilium
Claim this toolCloud native networking, observability, and security powered by eBPF.
Free plan available, paid tiers aboveVisit WebsiteFreemiumVisit Website
Tracked since2026
The Bottom Line
- Price
- Free plan available, paid tiers above. Compare plans
Key facts
- eBPF-based networking, observability, and security for cloud native environments.
- Provides high-performance data path and granular policy enforcement in Kubernetes.
- Offers deep visibility into network traffic and application behavior.
Pros
- High performance due to eBPF kernel-level operation
- Granular security policies based on workload identity
- Deep visibility into network and application traffic
- Seamless integration with Kubernetes
- Reduces need for sidecar proxies for certain functions
Cons
- Requires understanding of eBPF and advanced networking concepts
- Can have a steeper learning curve for new users
- Configuration complexity can increase with advanced use cases
What is Cilium?
Cilium is an open-source project that provides networking, observability, and security for cloud native environments, particularly Kubernetes. It leverages eBPF (extended Berkeley Packet Filter) technology to offer high-performance data path capabilities directly within the Linux kernel, enabling advanced features without requiring kernel module changes or sidecar proxies.
This tool is designed for organizations deploying and managing containerized applications, especially those using Kubernetes. It addresses critical needs for network connectivity, traffic management, policy enforcement, and deep visibility into network activity within complex microservices architectures. By operating at the kernel level, it offers superior performance and granular control compared to traditional networking solutions.
Key benefits include enhanced security through identity-based policy enforcement, improved network performance, and comprehensive observability into network flows, DNS requests, HTTP/gRPC traffic, and more. It helps platform engineers, SREs, and security teams build more resilient, secure, and performant cloud native applications.
Available on: Linux
Preview
Key Features
- eBPF-powered data path
- Identity-based security policies
- Kubernetes-native integration
- Advanced network observability (L3-L7)
- Load balancing (Service Mesh, Ingress, Egress)
- Multi-cluster connectivity
- Transparent encryption
- DNS-aware policies
Pricing
Freemium
Cilium offers a generous free tier with optional paid upgrades for advanced features.
Reviews
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Cilium FAQ
How does Cilium enhance security in cloud-native environments?
Cilium enhances security through identity-based policy enforcement, allowing granular control over network communication between workloads. It provides deep visibility into network flows, DNS requests, and HTTP/gRPC traffic, which aids in identifying and mitigating security threats. This approach helps security teams build more secure cloud-native applications.
What kind of user or team benefits most from using Cilium?
Cilium is best suited for platform engineers, SREs, and security teams managing containerized applications, especially within Kubernetes environments. These teams benefit from its capabilities in network connectivity, traffic management, and policy enforcement for complex microservices architectures. It helps them achieve more resilient, secure, and performant cloud-native applications.
How does Cilium compare to a service mesh like Istio?
Cilium differentiates itself from Istio by leveraging eBPF technology for high-performance data path capabilities directly within the Linux kernel. This allows it to offer advanced networking, observability, and security features without always requiring sidecar proxies, which can be a common pattern in service meshes like Istio. Cilium focuses on kernel-level operation for superior performance and granular control.
What are the main trade-offs when implementing Cilium?
The main trade-offs when implementing Cilium include a potentially steeper learning curve for new users due to its reliance on eBPF and advanced networking concepts. Additionally, the configuration complexity can increase significantly when deploying advanced use cases. Users should be prepared to invest time in understanding these underlying technologies.
How is Cilium priced?
Cilium is available on a free tier, allowing users to get started without initial cost. For organizations requiring more extensive usage or additional features, paid plans are offered. These paid plans provide enhanced capabilities to meet advanced operational needs.
Can Cilium provide detailed insights into application traffic?
Yes, Cilium provides comprehensive observability into network and application traffic. It offers deep visibility into network flows, DNS requests, and HTTP/gRPC traffic. This allows for detailed monitoring and troubleshooting of communication within microservices architectures.
How does Cilium achieve high network performance?
Cilium achieves high network performance by leveraging eBPF (extended Berkeley Packet Filter) technology, which operates directly within the Linux kernel. This enables high-performance data path capabilities without requiring kernel module changes or sidecar proxies. By operating at the kernel level, it offers superior performance compared to traditional networking solutions.
Source: cilium.io