Port 500 is used for IKE traffic from the VPN client to server.
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Introduction
IKE uses UDP port 500 for the initial phase of establishing a secure tunnel. This phase is also known as the IKE phase 1 exchange. The purpose of phase 1 is to negotiate security policies and cryptographic options that will be used during phase 2.
IKE uses different ports for different phases of the secure tunnel establishment process. During phase 1, IKE uses UDP port 500 to negotiate security policies and cryptographic options that will be used during phase 2.
What is UDP?
UDP is a connectionless protocol that runs on top of IP. UDP provides no guarantees to delivery or ordering of messages and there is no overhead for maintaining a connection. Because of this, UDP is sometimes called the “unreliable” protocol. Although UDP is unreliable, it has less overhead and is therefore faster than TCP. For this reason, UDP is used for applications that require speed such as video streaming and online gaming
What is IKE Traffic?
IKE traffic is responsible for creating and maintaining secure VPN connections. It uses a variety of protocols and ports to accomplish this, including UDP 500, UDP 4500, and ESP.
What is the Difference Between UDP and IKE Traffic?
UDP, or User Datagram Protocol, is a method of sending data over the internet. It is different from TCP, or Transmission Control Protocol, in that it does not require a connection to be established between the two devices before sending data. This makes UDP faster and more efficient for certain tasks, such as streaming audio or video.
IKE, or Internet Key Exchange, is a protocol used to set up a secure connection between two devices. IKE uses UDP port 500 to communicate between the VPN client and server.
How to Configure IKE Traffic on Your Router
To configure IKE traffic on your router, follow these instructions:
1. Navigate to the router’s web interface.
2. Find thezekrouter’s settings for IKE traffic.
3. Enable IKE traffic on the router.
4. Save the settings and restart the router for the changes to take effect.
Conclusion
As IKE uses UDP port 500, any IKE traffic sent to or from a VPN client or server will use this port. It’s important to ensure that this port is open on any firewall between the client and server, as blocking it will prevent IKE from working properly.