Advantage of Key Agreement Protocol

A new key exchange protocol has been created that extends the IKE protocol, which uses IPSec to negotiate SAs to protect AH and ESP traffic. The new key exchange protocol is Authenticated Internet Protocol (AuthIP). AuthIP is an extension of the current IKE, but provides additional support for the mode of transport to make it more efficient. It is designed to simplify the key exchange process by reducing the complexity and number of round trips required. In the classic key exchange, the exhaustive search for the right long-term key by construction may simply not be feasible: it is completely random and very long. A password, on the other hand, is likely to be short and generated with less than ideal randomness from a small set of values, allowing for a full search. We illustrate the effects of this phenomenon with a „fake“ protocol. FC-SP is a security infrastructure that includes protocols to improve Fibre Channel security in a variety of areas, including Fibre Channel device authentication, cryptographically secured key exchange, and cryptographically secured communication between Fibre Channel devices. FC-SP focuses on protecting data in transit over the Fibre Channel network. FC-SP is not concerned with the security of data stored on the Fibre Channel network. Many key exchange systems allow one party to generate the key and simply send that key to the other party – the other party has no influence on the key. Using a key matching protocol avoids some of the key distribution issues associated with such systems. The exponential exchange of keys in itself does not specify any prior agreement or subsequent authentication between participants.

It has therefore been described as an anonymous key memorandum of understanding. A common mechanism for repelling such attacks is the use of digitally signed keys, which must be secured by integrity: if Bob`s key is signed by a trusted third party who vouches for her identity, Alice may have considerable confidence that a signed key she receives is not an attempt to be intercepted by Eve. If Alice and Bob have a public key infrastructure, they can digitally sign an agreed Diffie-Hellman key or exchange Diffie-Hellman public keys. These signed keys, sometimes signed by a certificate authority, are one of the main mechanisms used to secure web traffic (including HTTPS, SSL, or Transport Layer Security protocols). Other concrete examples are MQV, YAK and the ISAKMP component of the IPsec protocol suite to secure Internet Protocol communication. However, these systems require precautions to confirm that the mapping between identity information and public keys by certification authorities is working properly. The key management protocol is designed to have the following features: To avoid the use of additional out-of-band authentication factors, Davies and Price suggested using Ron Rivest and Adi Shamir`s Interlock protocol, which underwent both attacks and subsequent improvements. It is not easy to use passwords instead of long, cryptographically strong keys to authenticate key exchange protocol flows. For example, a password cannot simply replace a strong symmetric key as input for a traditional key exchange protocol. There are two main reasons for this.

Password-authenticated key matching protocols require that you configure a password separately (which may be smaller than a key) in a way that is both private and secure. These are designed to resist man-in-the-middle and other active attacks on the password and established keys. For example, DH-EKE, SPEKE, and SRP are password-authenticated variants of Diffie-Hellman. Client: UE A and UE B clients are registered under the different SIP proxy servers (A and . B, respectively). For the exchange of session keys between UE A and UE B, the operation was performed on the basis of the Diffe-Hellman key exchange protocol to ensure perfect confidentiality and prevent key attacks. Figure 7.1(b) illustrates the TW-KEAP method of exchanging keys between UE A and UE B. Dictionary attacks are specific to PAKE protocols. However, the transmission secrecy and security of known session keys were taken into account in the classic key exchange and then transferred in the password-based case.

It can be tempting to do this with all the security features that can be set for key exchange in general, but this is not always possible. For example, resistance to identity theft with key compromises, in which an attacker who has compromised a user`s long-term key can then impersonate other parts of that user, is not satisfied by a PAKE: the other owner of the password can still be imitated as an attacked user. One of the advantages of MIKEY is that the key can be negotiated during the session configuration phase in SIP as part of the SDP payload. Thus, no additional communication effort is required. An obvious disadvantage of MIKEY is that it requires either previous shared secrets or a separate public key infrastructure, with all the associated issues such as certificate distribution, revocation, etc. This type of attack is arguably the most important to prevent in the PAKE design, as an attacker doesn`t need to be online to execute it. Offline attackers have more computing time and power for the simple reason that they cannot be interrupted. In fact, in the example above, it was enough for the opponent to record an exchange. From then on, there is no longer any way to interfere with the behavior of the adversary. We call such attacks offline dictionary attacks. To prevent them, it is necessary that the protocol does not reveal a single piece of information about the underlying password, even if the attacker deals with the protocol and injects their own data while trying to impersonate a party.

This has an important consequence for authentication; We will come back to this later. In 1976, Whitfield Diffie and Martin Hellman published a cryptographic protocol called diffie-Hellman Key Exchange (D-H) based on concepts developed by Hellman graduate student Ralph Merkle. The protocol allows users to securely exchange secret keys, even if an adversary monitors this communication channel. However, the D-H key exchange protocol does not deal with authentication (i.e. .dem problem of being sure of the real identity of the person or „entity“ at the other end of the communication channel). Authentication is crucial when an adversary can both monitor and modify messages in the communication channel (AKA man-in-the-middle or MITM attacks) and has been discussed in the fourth section of the document. [2] Multimedia Internet KEYing (MIKEY) is another key exchange protocol for SRTP defined in RFC 3830.12. It is mainly intended for peer-to-peer, simple one-to-many and small (interactive) groups. One of the most important multimedia scenarios considered when designing MIKEY was the conversational multimedia scenario, where users can interact and communicate in real time. In these scenarios, peers are expected to establish media sessions among themselves, where a media session can consist of one or more secure media streams (e.B. SRTP streams).

Here are some typical scenarios involving multimedia applications that can occur: Online dictionary attacks are active attacks in which the attacker tries to guess the password through successive login attempts: the adversary continues to deal with the protocol, trying different passwords, and when the opposing party stops having an abortion, the opponent knows that he has guessed the right password. It is clear that the design of the protocol cannot prevent this attack. However, a well-built PAKE should only allow you to test one password per login attempt. From that point on, it is up to the application that supports the protocol to specify how many unsuccessful attempts can be tolerated before, for example, the target account is locked. If you have a secure way to verify a shared key on a public channel, you can perform a Diffie-Hellman key exchange to derive a shared key in the short term and then authenticate that the keys match. One option is to use a reading authenticated by the key language, as in PGPfone. However, voice authentication presupposes that it is not possible for a man in the middle to falsify one participant`s voice in real time for the other, which can be an undesirable hypothesis. Such protocols can be designed to work even with a small public value, e.B a password. Variants of this theme have been suggested for Bluetooth pairing protocols.

In cryptography, a key memorandum of understanding is a protocol in which two or more parties can agree on a key in a way that influences the outcome. If done correctly, it prevents undesirable third parties from imposing a key choice on the parties. Protocols that are useful in practice also do not reveal to spies which key has been agreed. MIKEY can be integrated into session configuration minutes. Currently, the integration of MIKEY into SIP/SDP and RTSP is defined in KMASDP.13 MIKEY can use other transports, in which case it is necessary to define how MIKEY is transported on such a transport protocol. A user`s password in a PAKE protocol is considered a long-term key (that is, it should be used multiple times to create random, independent session keys). It obviously plays a role in calculating session key swap logs and can even appear as an argument to the formula that generates the session keys themselves. .

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