What is main mode in VPN?

Main Mode ensures the identity of both VPN gateways, but can be used only if both devices have a static IP address. Main Mode validates the IP address and gateway ID. Aggressive Mode is faster but less secure than Main Mode because it requires fewer exchanges between two VPN gateways.

Why do we use aggressive mode?

The result is that Main mode protects the identity of the ISAKMP servers while Aggressive mode does not. Aggressive mode provides a mechanism to exchange certificates when signature-based authentication is used.

What is main mode and quick mode?

Main mode and quick mode are IPsec generic terms referring to the stages of the IPsec negotiation process for securely exchanging encryption keys between hosts. An IPsec connection is set up using the more resource intensive main mode negotiation, aka IKE phase one.

What is the main weakness of IKE aggressive mode?

Using Aggressive Mode with pre-shared keys exposes inherent vulnerabilities with Aggressive Mode’s Phase 1 clear-text exchange. These vulnerabilities are exaggerated via short key lengths or insecure encryption algorithms.

What’s the difference between Main and aggressive mode VPN?

The VPN security risks in question relates to that first phase. It can happen in either of two ways: Main Mode, which uses a secure, encrypted, six-way handshake; and Aggressive Mode, which uses a three-way handshake that involves sending a pre-shared key (PSK) from the “responder” (device) to the “initiator” (client) unencrypted .

What’s the difference between Quick Mode and aggressive mode?

This phase is referred to as Quick Mode. Main Mode uses a six-way handshake where parameters are exchanged in multiple rounds with encrypted authentication information. Aggressive Mode uses a three-way handshake where the VPN sends the hashed PSK to the client in a single unencrypted message.

How to get rid of aggressive mode on Ike VPN?

Disable Aggressive Mode and only allow Main Mode when possible. Consider using certificates to authenticate clients that have dynamic IP addresses so that Main Mode can be used instead of Aggressive Mode. Use a very complex, unique PSK, and change it on a regular basis.

What kind of handshake does a VPN use?

Main Mode uses a six-way handshake where parameters are exchanged in multiple rounds with encrypted authentication information. Aggressive Mode uses a three-way handshake where the VPN sends the hashed PSK to the client in a single unencrypted message.