What is IKEv2?

IKEv2 (Internet Key Exchange version 2) is an encrypted tunneling protocol VPNs use that is responsible for securing internet traffic.

what is IKEv2

IKEv2 (Internet Key Exchange version 2) is an encrypted tunneling protocol VPNs use that is responsible for securing internet traffic.

IKEv2 is a protocol that provides authenticated keying material for Internet Protocol security (IPsec). IKEv2 replaced the IKE (RFC 2409) mechanism, also known as “IKE Phase 1”. The same protocol can be used to negotiate either IPsec VPN connections or the actual encryption and authentication algorithms for them.IKEv2 is used with IPsec to implement secure exchange of packets at the IP layer.

When a VPN connection is established, a number of parameters are securely exchanged. For example, an IKE Phase 1 negotiation involves the offer and response of several Diffie-Hellman public values, nonce – or “cookies” -and session-specific information.

In the IKE Phase 2 negotiation, additional security associations are established which can be used to transport data packets or configure a secure Virtual Private Network (VPN) tunnel.  IKEv2 in itself is a key management protocol (generation, exchange, and use of keys that help your device and a VPN server recognize each other) that is used together with IPsec.

In summary, IKEv2 is a key-focused protocol that makes public exchanges of cryptographic parameters between two entities and it creates security associations for them by using Diffie-Hellman key exchange.

What does an IKEv2 VPN do?

IKEv2 (Internet Key Exchange version 2) is the most commonly used authentication method for IPsec. It provides security for network traffic by authenticating and encrypting each packet of a data stream.

It’s secure because the connection is initiated from both sides, so there’s no opportunity to inject packets from outside sources.

The protocol also terminates when it detects a drop in connection quality, so your data isn’t being sent if it’s not safe to do so.

IKE builds upon the Oakley Key Determination Protocol and ISAKMP, both of which define widely accepted methods for two devices.

The IKEv2 VPN protocol also comes with a NAT traversal mode. This allows for secure communications even when the devices are behind a network address translation (NAT) device, such as a firewall or router.

It does this by using UDP port 500 and 4500 and IKE to create security associations (SAs) and Security Parameter Indexes (SPIs) to authenticate and encrypt the data.

Modes of IKEv2

IKEv2 operates in two modes:

No NAT mode – used when both endpoints are on public IP addresses. In this case, it doesn’t matter if the devices are behind a NAT device.

NAT traversal mode – uses UDP ports 500 and 4500 to send encrypted packets through a NAT device from one endpoint to another.

When should I use IKEv2?


IKEv2 is a newer, stronger standard for establishing secure connections between two network devices.

It is used by most VPN service providers to establish the initial connection with their users’ devices before passing traffic onto OpenVPN or other protocols.

Using a Diffie–Hellman key exchange algorithm, the protocol sets up a secure communication channel between your device and the VPN server. 

IKEv1 was originally designed as an interoperability replacement for Cisco’s proprietary IPSec VPN protocol. It served this purpose well and is still in widespread use today.

However, it has some important security vulnerabilities that make it an unsafe choice for certain types of VPN connections.

IKEv2 was designed to resolve these issues. It uses stronger cryptography (for example, mandates the use of AES-256 rather than DES or 3DES)and offers a number of security improvements over IKEv1.

In addition to this, it also supports MOBIKE – a feature that allows for the creation of redundant VPN connections from devices behind NAT firewalls.

This makes it an ideal choice for mobile users who connect through wireless hotspots and other types of unstable internet connections.

WhileIKEv1 is still safe to use, it lacks the security improvements of IKEv2. For this reason, most VPN services providers have started offering IKEv2 connections instead of or in addition to IKEv1.

What is the difference between VPN and IKEv2?

Let’s discuss IKEV2, IPSEC in detail! VPN(Virtual Private Network) has been used in our daily life. It’s a convenient and fast way that internet resources can be accessed from anywhere at any time. In recent years, VPN technology has been developing very quickly.

New types of VPN protocols emerge in succession, but they have not fundamentally improved user experience.

VPN works by creating a secure and encrypted internet connection that can only be accessed by the user with the right username and password, all other users on this network are blocked. But VPN protocols are not new technology. Most of them were created ten years ago or even older. They rely on insecure SSL/TLS encryption algorithms for security.

VPN is still an easy-to-use method for hiding activity and protecting data, but it is not without its disadvantages. The main disadvantage is that VPNs are very slow because the user will first connect to the server before accessing other websites or servers.

During this process, packets will be converted between secure SSL/TLS and insecure HTTP transmission. Then the connection speed directly depends on the performance of the VPN server and the user’s ISP.

VPN is also very easy to implement, but it has no seamless connection mode across multiple devices, unlike IKEv2. It’s necessary to configure each device separately by assigning the same username, password, and profile for all devices that need to access the VPN before using it. This could be a headache for users.

IKEv2 is a new protocol that was originally developed by Microsoft in 1999, improved by Cisco in 2004, and standardized by the IETF in 2010. Its official name is Internet Key Exchange version 2. Compared with legacy VPN protocols, IKEv2 has many obvious advantages: fast connection speed, multi-device seamless connection capability, strong security, and high adaptability to dynamic changes in network environments.

Since IKEv2 is a major improvement on the existing VPN protocols, so many products have integrated this protocol after 2010. For example Windows 8, Blackberry 10, Blackphone, etc. These products can switch from the internet to the local intranet without any inconvenience for users.

When a user changes from one wifi connection to another, the VPN will switch over automatically. In this way, users can continue tasks without interruption. IKEv2 supports the standard PFS(Perfect Forward Secrecy).


This means that if an attacker steals a user’s authentication credential and key material in the future, they still won’t be able to decrypt the user’s recent communications. The Internet security association ensures VPN providers with other VPN protocols to promote IPSEC VPN configurations.

IKEv2 is secure, fast, and easy to use. It has already become more and more popular around the world in recent years. But this protocol is still not perfect. Now, IKEv2 is supported by many products on Windows, iOS, Android, etc., but its support for Linux and other operating systems is still very poor. IKEv2 needs to be improved from the perspective of cross-platform support.

In conclusion, VPN is a more mature technology with higher security requirements than IKEv2. But nowadays, VPN users have to pay for it because it’s not free. Those who are concerned about privacy will buy a VPN service. It offers a very secure protocol to VPN providers with underlying security protocols to get internet traffic for the authentication suite.

And IKEv2 is a more promising technology with high flexibility, fast speed, and multi-platform support. It’s freeware for users on almost every platform on the market today.



Home » VPN » VPN Glossary » What is IKEv2?

Join our newsletter

Subscribe to our weekly roundup newsletter and get the latest industry news & trends

By clicking 'subscribe" you agree to our terms of use and privacy policy.