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Cloud · head to head

Cilium vs OpenVPN

Cilium logo

Cilium

Cloud

eBPF-based networking, observability and security for Kubernetes

From
Free
Rated
-
Full reviewWebsite
OpenVPN logo

OpenVPN

Networking

Open source VPN protocol with a commercial Access Server product priced per simultaneous connection

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Cilium requires a recent Linux kernel, which rules out older distributions and some managed environments; OpenVPN open source OpenVPN, while free, requires real technical skill to configure, secure and maintain without the Access Server admin layer
  • They diverge on capability: Cilium covers eBPF datapath, OpenVPN covers Open source core.
  • Prices and features above were last checked on 1 September 2026.

Where they differ

Only the attributes on which Cilium and OpenVPN actually diverge.

Attributes where Cilium and OpenVPN differ
AttributeCiliumOpenVPN
Pricing modelOpen source, no licence feeOpen source core is free; Access Server billed per simultaneous connection
PlatformsKubernetes, LinuxLinux, Windows, macOS, iOS, Android
CategoryCloudNetworking

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Cilium

  • eBPF datapath
  • Identity-based policy
  • Hubble observability
  • Sidecar-free mesh

Only in OpenVPN

  • Open source core
  • Access Server admin UI
  • Per-connection licensing
  • Free tier
  • Cross-platform clients

What people use each for

The jobs each tool is most often brought in to do.

Cilium

  • Kubernetes networking at a scale where iptables-based CNI performance degradesnot OpenVPN
  • Network policy expressed on workload identity rather than fragile IP rulesnot OpenVPN
  • Seeing which services actually talk to each other, and what policy is droppingnot OpenVPN

OpenVPN

  • A technical team wanting a fully free, self-configured VPN server using the open source protocol without any vendor relationshipnot Cilium
  • A small business wanting a supported, easier-to-administer VPN server, willing to pay per concurrent connection rather than per employeenot Cilium
  • An organisation with more staff than typical concurrent VPN usage, since Access Server bills only active simultaneous connections, not total accountsnot Cilium
  • An IoT or large-scale deployment needing custom Enterprise pricing above 2,000 connectionsnot Cilium

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Cilium

  • Requires a recent Linux kernel, which rules out older distributions and some managed environments
  • eBPF is genuinely hard to debug when it misbehaves, and the skill is rare on most teams
  • Broad scope — CNI, policy, mesh, observability — means the learning curve covers several domains at once

OpenVPN

  • Open source OpenVPN, while free, requires real technical skill to configure, secure and maintain without the Access Server admin layer
  • Per-connection billing on Access Server means usage spikes, such as an all-hands remote day, can push simultaneous connections over a licensed limit and block new connections until usage drops or the plan is upgraded
  • OpenVPN's traditional hub-and-spoke architecture routes traffic through a central server, unlike mesh VPN tools like Tailscale or NetBird that establish direct peer-to-peer connections where possible, which can add latency
  • Client configuration and certificate management for the open source version is more manual and error-prone than newer VPN tools with zero-config onboarding
  • Access Server pricing above the Growth tier reverts to custom Enterprise quoting, so very large deployments lose the pricing transparency of the lower tiers
  • The protocol's throughput is generally lower than newer kernel-integrated protocols like WireGuard under equivalent conditions, which matters for high-bandwidth use cases

Pricing, plan by plan

Cilium

Free
  • CiliumFree
    • Full functionality
    • No usage limits
    • Community support

OpenVPN

Free
  • Access Server FreeFree
    • Up to 2 simultaneous connections
    • All features included
  • Access Server Growth$7/month
    • Per simultaneous connection beyond the free tier
    • Annual billing
  • Access Server Enterprise/IoT$undefined/month
    • Custom pricing for 2,000+ connections

Which should you pick?

Choose Cilium if

  • You need ebpf datapath.
  • You want to start without paying.
  • You work on Kubernetes, Linux.
  • You also want identity-based policy.
Cilium review

Choose OpenVPN if

  • You need open source core.
  • You want to start without paying.
  • You work on Linux, Windows, macOS, iOS, Android.
  • You also want access server admin ui.
OpenVPN review

Questions people ask

Is Cilium or OpenVPN better?
Neither clearly leads. Cilium starts at Free and OpenVPN at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Cilium or OpenVPN?
Cilium starts at Free and OpenVPN at Free.
Does Cilium or OpenVPN run on more platforms?
Cilium runs on Kubernetes, Linux. OpenVPN runs on Linux, Windows, macOS, iOS, Android.
Can I use Cilium for free?
Both have a free tier, so you can try either at no cost before committing.
What is Cilium best used for?
Cilium is most often used for kubernetes networking at a scale where iptables-based cni performance degrades, network policy expressed on workload identity rather than fragile ip rules, seeing which services actually talk to each other, and what policy is dropping. Of those, kubernetes networking at a scale where iptables-based cni performance degrades and network policy expressed on workload identity rather than fragile ip rules are not what OpenVPN is typically brought in for.
What can Cilium do that OpenVPN cannot?
Cilium covers eBPF datapath, Identity-based policy, Hubble observability, Sidecar-free mesh. OpenVPN covers Open source core, Access Server admin UI, Per-connection licensing, Free tier.

Answered from the vendors’ own pages

Cilium: Is Cilium free?

Yes, open source and CNCF-graduated. Isovalent sells an enterprise distribution and support.

OpenVPN: Is OpenVPN free?

The open source protocol and software are free under the GPL; Access Server, the commercial packaged product, charges per simultaneous connection beyond a free 2-connection tier.

Cilium: What does eBPF change?

It lets Cilium run packet-processing programs inside the kernel instead of relying on iptables rule chains, which behave poorly as the number of services grows.

OpenVPN: What counts as a connection for billing purposes?

A simultaneously active connected device, not a registered user account or total device count; unlimited accounts and devices can be created but only the licensed number can be connected at once.

Cilium: Does Cilium replace a service mesh?

It can cover much of what a mesh does without sidecars, though full mesh feature sets still favour Istio or Linkerd.

OpenVPN: How does OpenVPN compare with WireGuard-based tools like Tailscale?

OpenVPN uses a traditional hub-and-spoke VPN architecture rather than the mesh, peer-to-peer approach used by newer tools like Tailscale or NetBird.

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