Description (as of October 2023):

In the next LCOS Major Release the obsolete and insecure encryption algorithms CAST128-CBC, Blowfish-CBC and DES-CBC will be eliminated in the firmware and therefore won't be available anymore. Corresponding VPN connections then won't be functional anymore. LCOS 10.80 will be the last Firmware with support for the mentioned encyrption algorithms.

LANCOM Systems recommends to select the option AES-CBC in the field Encryption under VPN → IKE/IPSec → IKE proposals beforehand, if IKEv1 must still be used.

In 2019 the IETF (Internet Engineering Task Force) has designated IKEv1 as deprecated and insecure and therefore it should not be used anymore. LANCOM Systems instead recommends to use the current standard IKEv2.

The IKEv1 functionality in LANCOM devices remains intact and can still be used for scenarios where devices without IKEv2 support are used. However LANCOM Systems will not provide any support regarding the troubleshooting of connection problems with IKEv1 connections. Also there won't be any bug fixes or new features for IKEv1.

No action is required if IKEv2 is used, as these algorithms aren't used there. The LMC excklusively uses IKEv2 for VPN connections.