IKEv2 VPN Protocol Explained: What It Is and How It Works

How Does IKEv2 Work?

IKEV2 heavily relies on IPSec to secure the communication between a VPN client and a VPN server.

This explains why the protocol is often identified as IKEv2/IPSec. Simply put, IKEv2/IPSec secures and allows the exchange of encryption keys – true to its name.

In a nutshell, IKEV2 sets up a security association (SA) that negotiates security keys used by both the VPN client and the VPN server.

Once IKEv2 validates the security association, a secure tunnel is set, which prompts encrypted communication between the two peers.

IKEv2/IPSec uses the more robust 256-bit encryption. It can use VPN encryption ciphers such as AES, ChaCha20, and Camellia.

The VPN protocol also uses the famous Diffie-Hellman Key Exchange algorithm to secure private key exchange.

It’s also worth knowing that:

• IKEv2 supports Perfect Forward Secrecy (PFS) for data integrity and complete secrecy.
• IKEv2/IPSec uses UDP packets as well as port 500.
• IKEv2 uses X.509 certificates for authentication.
• IKEv2 integrates well with open-source software like OpenIKEv2, StrongSwan, OpenSwan, and more.

Why is IKEv2 Always Paired with IPSec?

It’s all about security, speed, and stability. IPSec is renowned for its security and reliability, while IKEv2 stands out for its exceptional speed and stability, especially when reconnecting quickly during network changes or sudden drops.

Combining IKEv2 and IPSec creates one of the most effective VPN protocols, leveraging the strengths of both technologies.

The IPSec protocol suite establishes secure tunnels between two communicating peers over a network and is used to encrypt data in VPNs.

Additionally, IPSec employs various techniques for authentication and key exchange to negotiate security associations, with Internet Key Exchange (IKE and IKEv2) being among the most prominent.

Why is IKEv2 Considered Better than IKEv1?

IKEv2 is the successor of IKEv1, with improvements and optimizations such as fast speeds, greater security, and increased efficiency.

Here is a highlight of the features of the improved IKE version 2:

• IKEv2 supports more encryption algorithms, including Asymmetric authentication
• IKEv2 is more stable thanks to its support for Mobility and Multi-homing Protocol (MOBIKE)
• IKEv2 uses fewer bandwidth data by using a reduced number of security associations needed
• IKEv2 features a built-in NAT traversal which enables it to pass through firewalls
• IKEv2 can determine if a tunnel is active, thanks to its ‘keep alive’ feature that’s always enabled
• IKEv2 supports an authentication technique called Extensible Authentication Protocol (EAP) that secures communication
• IKEv2 is highly reliable, thanks to its enhanced number sequence and acknowledgments
• IKEv2 is more resistant to DoS attacks because of its ability to check and determine if a requester exists before it takes any action

IKEv2 Compatibility

IKEv2 supports all major platforms, including Windows, macOS, Android, iOS, Linux, and routers.

It’s especially fast on macOS, making IKEv2 VPNs great choices if you are looking for a Mac VPN.

The protocol is also compatible with smart devices like Smart TVs and some streaming devices.

Most VPN providers offer IKEv2/IPSec as a default protocol on their client apps due to its advanced security, stability, and reliability levels.

Benefits of the IKEv2/IPSec Protocol

• Very fast, regardless of using strong encryption levels.
• Very secure as it uses multiple advanced ciphers for maximum protection.
• Very stable thanks to its seamless auto-reconnect feature let users switch between networks without dropping protection or connection.
• Compatible with all major platforms and devices.

Disadvantages of the IKEv2/IPSec Protocol

• IKEv2 is closed source, thus raising slight security concerns, coupled with its links to Microsoft and Cisco. Some implementations are open source.
• IKEv2 can be exploited since it is built upon ISAKMP.

2024 Update: The IKEv2 (Internet Key Exchange version 2) VPN protocol continues to be recognized for its speed and security, making it a highly recommended choice for VPN users. It’s advisable to opt for IKEv2 whenever you’re using a VPN for optimal performance and enhanced security.