OpenConnect Server vs strongSwan

A side-by-side comparison of two self-hosted remote access & vpn options — licensing, setup difficulty, resource needs, and what each one replaces.

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FeatureOpenConnect ServerstrongSwan
Deploy effortUnder-an-hour setupRead-the-docs project
CategoryRemote Access & VPNRemote Access & VPN
LicenseGPL-2.0GPL-2.0
LanguageCC
Setup difficultyHardHard
Min. RAM128 MB128 MB
Deploymentbare-metal, dockerbare-metal, binary
GitHub stars★ 600★ 2,987
First released20132005
ReplacesCisco AnyConnectCisco AnyConnect

What are OpenConnect Server and strongSwan?

OpenConnect Server

ocserv is an open-source SSL VPN server that implements the OpenConnect protocol and is compatible with Cisco AnyConnect clients. It supports multiple authentication backends.

  • AnyConnect-compatible
  • Multiple auth backends
  • Low resource use
  • Per-user configuration

strongSwan

strongSwan is a complete IPsec implementation for Linux and other platforms supporting IKEv1 and IKEv2 key exchange. It is widely used for site-to-site and remote access VPNs.

  • Full IPsec implementation
  • IKEv1 and IKEv2 support
  • Certificate-based auth
  • Cross-platform

OpenConnect Server vs strongSwan: key differences

Both projects are written in C. StrongSwan is the more established project (first released 2005), while OpenConnect Server arrived in 2013. StrongSwan has the considerably larger community, at 2,987 GitHub stars versus 600. OpenConnect Server lists first-class Docker deployment; strongSwan does not.

Why pick each one

Choose OpenConnect Server if…

  • Released under the GPL-2.0 license
  • First-class Docker support for quick deployment
  • Written in C
  • Tiny footprint — runs in 128 MB RAM
OpenConnect Server details

Choose strongSwan if…

  • Released under the GPL-2.0 license
  • Active community (3k GitHub stars)
  • Written in C
  • Tiny footprint — runs in 128 MB RAM
strongSwan details

Frequently asked questions

Is OpenConnect Server or strongSwan better?

Neither is universally better. strongSwan has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.

Are OpenConnect Server and strongSwan free and open-source?

Yes. OpenConnect Server is licensed under GPL-2.0 and strongSwan under GPL-2.0. Both can be self-hosted at no software cost.

Can I run OpenConnect Server and strongSwan with Docker?

OpenConnect Server: yes. strongSwan: check the project docs for container support.

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