IKE traffic is responsible for VPN client to server communication and uses UDP port 500.
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IKE traffic between a VPN client and server uses UDP port 500.
What is VPN?
A VPN (Virtual Private Network) is a technology that creates a safe and encrypted connection over a less secure network, such as the internet. VPNs can be used to access region-restricted websites, shield your browsing activity from prying eyes on public Wi-Fi, and more. One of the most important uses of a VPN is allowing remote workers to securely connect to the company network.
What is IKE?
IKE (Internet Key Exchange) is a key management protocol that is used to setup a security association (SA) between two hosts. It uses a Diffie-Hellman key exchange to generate shared keys that can be used to encrypt and authenticate traffic. IKE runs over UDP port 500 and uses a number of different message types to perform its key exchange.
IKE traffic is the process of setting up a secure connection between a VPN client and server. IKE uses UDP port 500 for traffic from the VPN client to the server.
UDP Port 500
UDP port 500 is used for the initial phase of the IKE protocol when the VPN client and server first establish a connection. This phase, known as phase 1, uses Diffie-Hellman key exchange to generate a shared secret key that will be used to encrypt all subsequent communication between the client and server.
UDP Port 4500
UDP port 4500 is used for IKE traffic from VPN client to server. This is the standard port for IKE traffic.
In conclusion, IKE traffic from a VPN client to server uses UDP port 500.