• Journal of Internet Computing and Services
• /
• v.6 no.3
• /
• pp.17-30
• /
• 2005

A PAK(Password-Authenticated Key Exchange) protocol is used as a protocol to provide both the mutual authentication and allow the communication entities to share the session key for the subsequent secure communication, using the human-memorable portable short-length password, In this paper, we propose distributed key exchange protocols applicable to a smartcard using the MTI(Matsumoto, Takashima, Imai) key distribution protocol and PAK protocol. If only one server keeps the password verification data which is used for password authentication protocol. then It could easily be compromised by an attacker, called the server-compromised attack, which results in impersonating either a user or a server, Therefore, these password verification data should be distributed among the many server using the secret sharing scheme, The Object of this paper Is to present a password-based key exchange protocol which is to allow user authentication and session key distribution, using the private key in a smartcard and a password typed by a user. Moreover, to avoid the server-compromised attack, we propose the distributee key exchange protocols using the MTI key distribution protocol, And we present the security analysis of the proposed key exchange protocol and compare the proposed protocols with the existing protocols.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.10 no.4
• /
• pp.33-46
• /
• 2000

IPsec is a protocol suite to protect the data communication between computers on internet and many VPNs(Virtual Private Networks) use IPsec protocol. IKE protocol is used to exchange keys in IPsec. Formal analysis method is used increasingly in computer science to increase the reliability of a system. In this paper, the IKE protocol is analyzed formally. This paper shows that IKE with Authentication with Signature and Authentication with Pre-Shared Key is safe, but Authentication with Public Key Encryption and A Revised Method of Authentication with Public Key Encryption are safe only with the assumption that a participant has the correct public key of the correspondent. To make sure that a participant has the correct public key of the correspondent, the usage of certificate is recommended.

• Journal of KIISE:Information Networking
• /
• v.29 no.3
• /
• pp.324-332
• /
• 2002

We design authentication protocols for wireless internet not using certificates but using passwords. The target protocols include WTLS and the certificate request protocol in the wireless PKI(Public Key Infrastructure). When a password based protocol is designed and implemented for authentication and key exchange, care mutt be taken of the short length and of the not-so-randomness of passwords. To frustrate the offline guessing attack that makes use of those weaknesses, our two protocols are dependent on the password based authentication protocol that has security proof. In this paper, how to design systematically the security protocols for authentication and key exchange using passwords is presented, and the methodology hopes to be useful in some other area that needs authentication using passwords.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2008.05a
• /
• pp.917-920
• /
• 2008

The Internet Key Exchange (IKE) protocol is most widely used as a security key exchange protocol on the Internet. Security policies used by the IKE protocol must be configured in advance, however the complex options and manual settings cause inconvenience. This paper proposes an automatic configuration method for the IKE protocol based on X.509 certificate. Security policies are embedded in the certificate, read, and added into the IKE configuration file by a negotiation assistant module in order to achieve automatic IKE configuration. Our proposed method reduces the complexity of configuration process and improves the adaptability of the IKE protocol.

• Journal of Internet Computing and Services
• /
• v.9 no.2
• /
• pp.83-88
• /
• 2008

Session initiation protocol (SIP) is an application-layer prolocol to initiate and control multimedia client session. When client ask to use a SIP service, they need to be authenticated in order to get service from the server. Authentication in a SIP application is the process in which a client agent present credentials to another SIP element to establish a session or be granted access to the network service. In 2005, Yang et al. proposed a key exchange and authentication scheme for use in SIP applications, which is based on the Diffie-Hellman protocol. But, Yang et al.'s scheme is not suitable for the hardware-limited client and severs, since it requires the protocol participant to perform significant amount of computations (i.e., four modular exponentiations). Based on this observation. Huang and Wei have recently proposed a new efficient key exchange and authentication scheme thor improves on Yang et al.'s scheme. As for security, Huang and Wei claimed, among others, that their scheme is resistant to offline dictionary attacks. However, the claim turned out to be untrue. In this paper, we show thor Huang and Wei's key exchange and authentication scheme is vulnerable to on offline dictionary attack and forward secrecy.

• Journal of Internet Computing and Services
• /
• v.6 no.5
• /
• pp.27-43
• /
• 2005

EAP provides authentication for each entity based on IEEE Std 802.1x Wireless lAN and RADIUS/DIAMETER protocol, and it uses certificate, dual scheme(e.g., password and token) with the authentication method. The password-based authentication scheme for authenticated key exchange is the most widely-used user authentication method due to various advantages, such as human-memorable simplicity, convenience, mobility, A specific hardware device is also unnecessary, This paper discusses user authentication via public networks and proposes the Split Password-based Authenticated Key Exchange (SPAKE), which is ideal for both authenticating users and exchanging session keys when using a subsequent secure communication over untrusted network, And then we provides EAP authentication framework EAP-SPAKE by using it.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.199-202
• /
• 2003

IPsec is a standardization way for protection of IP packets in network layer and it is composed of three protocols that is AH(Authentication Header), ESP(Encapsulation Security Protocol) and IKE(Internet Key Exchange). Before doing encryption and decryption using AH or ESP protocols, both of communicating entities have to share same key safely. IKE protocol works automatically. But it has less interoperability because IKE protocol is not simple. A work which standardize IKEv2 has been done up to now. In this article, we will examine the Cryptographic Algorithms of IKEv2, and describe the AES usage with IPsec, based on the IETF Draft document.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.12
• /
• pp.6092-6115
• /
• 2017

This paper demonstrates a case for an end-to-end pure Application Security Layer for reliable and confidential communications within an Internet of Things (IoT) constrained environment. To provide a secure key exchange and to setup a secure data connection, Transport Layer Security (TLS) is used, which provides native protection against replay attacks. TLS along with digital signature can be used to achieve non-repudiation within app-to-app communications. This paper studies the use of TLS over the JavaScript Object Notation (JSON) via a The Constrained Application Protocol (CoAP) RESTful service to verify the hypothesis that in this way one can provide end-to-end communication flexibility and potentially retain identity information for repudiation. As a proof of concept, a prototype has been developed to simulate an IoT software client with the capability of hosting a CoAP RESTful service. The prototype studies data requests via a network client establishing a TLS over JSON session using a hosted CoAP RESTful service. To prove reputability and integrity of TLS JSON messages, JSON messages was intercepted and verified against simulated MITM attacks. The experimental results confirm that TLS over JSON works as hypothesised.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.42 no.10 s.340
• /
• pp.31-38
• /
• 2005

Ipsec is a security protocol suite that provides encryption and authentication services for IP messages at the network layer of the internet. Internet Key Exchange (IKE) is a protocol that is used to negotiate and provide authenticated keying materials in a protected manner for Security Associations (SAs). In this paper, we propose a dynamic key lifetime change algorithm for performance enhancement of virtual private networks using IPSec. The proposed algorithm changes the key lifetime according to the number of secure tunnels. The proposed algorithm is implemented with Linux 2.4.18 and FreeS/WAN 1.99. The system employing our proposed algorithm performs better than the original version in terms of network performance and security.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.2
• /
• pp.811-815
• /
• 2005

IPSec(Internet Protocol Security) is a framework for a set of protocols for security at the network or packet processing layer of network communication. IPSec is providing authentication, integrity and confidentiality security services. The specifications for Internet Key Exchange(IKEv1) were released to the world. Some criticisms of IKEv1 were that it was too complex and endeavored to define too much functionality in one place. Multiple options for multiple scenarios were built into the specification. The problem is that some of the included scenarios are rarely if ever encountered. For IPsec to work, the sending and receiving devices must chare a Public Key. This is accomplished through a protocol known as Internet Security Association and Key Management Protocol/Oakley(ISAKMP/Oakley), which allows the receiver to obtain a public key and authenticate the sender using digital certificates. This thesis is a study on the performance improvement of the security transmission using the SSFNet(Scalable Simulation Framework Network Models)