Systems Security Certified Practitioner – SSCP – Question0793

Which of the following is an Internet IPsec protocol to negotiate, establish, modify, and delete security associations, and to exchange key generation and authentication data, independent of the details of any specific key generation technique, key establishment protocol, encryption algorithm, or authentication mechanism?

A.
OAKLEY
B. Internet Security Association and Key Management Protocol (ISAKMP)
C. Simple Key-management for Internet Protocols (SKIP)
D. IPsec Key exchange (IKE)

Correct Answer: B

Explanation:

RFC 2828 (Internet Security Glossary) defines the Internet Security Association and Key Management Protocol (ISAKMP) as an Internet IPsec protocol to negotiate, establish, modify, and delete security associations, and to exchange key generation and authentication data, independent of the details of any specific key generation technique, key establishment protocol, encryption algorithm, or authentication mechanism.
Let’s clear up some confusion here first. Internet Key Exchange (IKE) is a hybrid protocol, it consists of 3 “protocols”
ISAKMP: It’s not a key exchange protocol per se, it’s a framework on which key exchange protocols operate. ISAKMP is part of IKE. IKE establishs the shared security policy and authenticated keys. ISAKMP is the protocol that specifies the mechanics of the key exchange.
Oakley: Describes the “modes” of key exchange (e.g. perfect forward secrecy for keys, identity protection, and authentication). Oakley describes a series of key exchanges and services.
SKEME: Provides support for public-key-based key exchange, key distribution centres, and manual installation, it also outlines methods of secure and fast key refreshment.
So yes, IPSec does use IKE, but ISAKMP is part of IKE. The questions did not ask for the actual key negotiation being done but only for the “exchange of key generation and authentication data” being done. Under Oakly it would be Diffie Hellman (DH) that would be used for the actual key nogotiation.
The following are incorrect answers:
Simple Key-management for Internet Protocols (SKIP) is a key distribution protocol that uses hybrid encryption to convey session keys that are used to encrypt data in IP packets.
OAKLEY is a key establishment protocol (proposed for IPsec but superseded by IKE) based on the Diffie-Hellman algorithm and designed to be a compatible component of ISAKMP.
IPsec Key Exchange (IKE) is an Internet, IPsec, key-establishment protocol [R2409] (partly based on OAKLEY) that is intended for putting in place authenticated keying material for use with ISAKMP and for other security associations, such as in AH and ESP. Reference used for this question: SHIREY, Robert W., RFC2828: Internet Security Glossary, may 2000.