Two routers running Cisco IOS Software are failing to negotiate the IPsec tunnel. Crypto debugs reveal the following messages:
1d00h: IPSec(validate_transform_proposal): proxy identities not supported 1d00h: ISAKMP: IPSec policy invalidated proposal 1d00h: ISAKMP (0:2): SA not acceptable!
What is the most likely cause of the error message? Select the best response.
A.
Crypto access lists are not mirrored on each side.
B.
The crypto-map is incomplete.
C.
ISAKMP policies have attributes that do not match.
D.
This is not an error message, but an indication that proxy IDs are not supported.