Techniques for passing security configuration information between a security policy server and a client includes the client forming a request for security configuration information that configures the client for secure communications. The client is separated by an untrusted network from a trusted network that includes the security policy sever. A tag is generated that indicates a generic security configuration attribute. An Internet Security Association and Key Management Protocol (ISAKMP) configuration mode request message is sent to a security gateway on an edge of the trusted network connected to the untrusted network. The message includes the request in association with the tag. The gateway sends the request associated with the tag to the security policy server on the trusted network and does not interpret the request. The techniques allow client configuration extensions to be added by modifying the policy server or security client, or both, without modifying the gateway.