GlossaryProtocolsIntermediate

IKEv2

IKEv2 is a fast, stable VPN protocol that is especially good at keeping your connection alive when you switch networks. It is commonly used on mobile devices for its speed and reliability.

Last updated June 8, 2026

Definition

IKEv2 (Internet Key Exchange version 2) is a VPN protocol used to set up a secure, authenticated tunnel. It is almost always paired with the IPsec suite for encryption, so it is commonly referred to as IKEv2/IPsec. Developed jointly by Microsoft and Cisco, it is known for speed and exceptional stability.

How IKEv2 works

IKEv2 handles the negotiation of security associations: it authenticates both parties and establishes shared encryption keys, while IPsec encrypts the actual data. Its standout feature is MOBIKE (Mobility and Multihoming), which lets a connection survive network changes, such as moving from Wi-Fi to cellular, without dropping the tunnel.

Why it matters

That seamless reconnection makes IKEv2 a favorite for mobile devices, where networks change constantly. It is fast, natively supported on iOS, Windows, and macOS, and quick to re-establish after interruptions.

  • Stable: auto-reconnects via MOBIKE.
  • Native support: built into most operating systems.
  • Trade-off: uses fixed UDP ports that firewalls can block.

For everyday mobile use, IKEv2 offers an excellent balance of speed, security, and reliability.

Examples

1

A phone seamlessly staying connected to a VPN while switching from Wi-Fi to 4G

2

iOS using its built-in IKEv2/IPsec client for a VPN profile

3

A VPN app defaulting to IKEv2 for fast mobile reconnection

Common Use Cases

Maintaining stable VPN connections on mobile devices
Quickly reconnecting after the network drops or changes
Securing iOS and Windows clients with native protocol support
Providing fast, low-latency VPN access for everyday browsing

Frequently Asked Questions

Yes, when paired with IPsec it supports strong encryption like AES-256 and is widely regarded as a secure, reliable VPN protocol.
Its MOBIKE feature lets the VPN tunnel survive network changes, so your connection stays alive when switching between Wi-Fi and cellular data.
Generally yes, IKEv2 tends to be faster and reconnects more quickly than OpenVPN, though WireGuard often outperforms both.

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All terms

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VPN

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SSL/TLS

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WireGuard

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