A proposal is a set of algorithms. For non-AEAD algorithms, this includes for IKE an encryption algorithm, an integrity algorithm, a pseudo random function and a Diffie-Hellman group. For AEAD algorithms, instead of encryption and integrity algorithms, a combined algorithm is used.
In IKEv2, multiple algorithms of the same kind can be specified in a single proposal, from which one gets selected. In IKEv1, only one algorithm per kind is allowed per proposal, more algorithms get implicitly stripped. Use multiple proposals to offer different algorithms combinations in IKEv1.
Algorithm keywords get separated using dashes. Multiple proposals may be specified in a list. The special value default forms a default proposal of supported algorithms considered safe, and is usually a good choice for interoperability.
StrongSwan default: ["default"]
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