2.20. Requesting the Peer's Version

An IKE peer wishing to inquire about the other peer's IKE software version information MAY use the method below. This is an example of a configuration request within an INFORMATIONAL exchange, after the IKE SA and first Child SA have been created.

An IKE implementation MAY decline to give out version information prior to authentication or even after authentication in case some implementation is known to have some security weakness. In that case, it MUST either return an empty string or no CP payload if CP is not supported.

Initiator                          Responder
-------------------------------------------------------------------
HDR, SK {CP(CFG_REQUEST)}  -->
                              <--  HDR, SK {CP(CFG_REPLY)}

CP(CFG_REQUEST)=
  APPLICATION_VERSION("")

CP(CFG_REPLY) APPLICATION_VERSION("foobar v1.3beta, (c) Foo Bar
  Inc.")

2.20. Requesting the Peer's Version​

2.20. Requesting the Peer's Version