Fuwen Liu

A survey of video encryption algorithms

The popularity of multimedia applications is rapidly growing nowadays. The confidentiality of video communication is of primary concern for commercial usage, e.g. in video on demand services or business meetings. A variety of video encryption algorithms have been proposed in order to fulfill the specific requirements raised by the peculiarities of video communication. Video encryption algorithms can be classified according to their association with video compression into joint compression and encryption algorithms, and compression-independent encryption algorithms. From this classification perspective, we give a complete survey of the representative video encryption algorithms proposed so far and present their properties and limitations. We show by comparing and assessing the surveyed schemes that each scheme has its own strengths and weaknesses and no scheme can meet all specific requirements. Hence, video applications have to select an appropriate video encryption algorithm that meets their confidentiality requirements.

A novel encryption algorithm for high resolution video

The popularity of multimedia applications is rapidly growing nowadays. The confidentiality of video communication is of primary concern for their commercial use, e.g. in video on demand services or in multiparty video conferences. Specific video encryption algorithms are strongly required in real-time multimedia communication to fulfill the strict timing requi-rements. In this paper we present a novel video encryption algorithm, called Puzzle, to encrypt video data in software. It is fast enough to meet real-time demands and provides a sufficient security. The algorithm can readily be incorporated into existing multimedia systems.

Cryptanalysis of a SIP authentication scheme

SIP (Session Initiation Protocol) is becoming the mostly deployed signaling protocol for VoIP (Voice over IP). Security is of utmost importance for its usage due to the open architecture of the Internet. Recently, Yoon et al. proposed a SIP authentication scheme based on elliptic curve cryptography (ECC) that claimed to provide higher security than other schemes. However, as demonstrated in this paper, it is still vulnerable to off-line dictionary and partition attacks.

Puzzle: a novel video encryption algorithm

Networked multimedia applications have matured in recent years to be deployed in a larger scale in the Internet. Confidentiality is one of the primary concerns of these services for their commercial usages, e.g. in video on de mand services or in video conferences. In particular, video encryption algorithms are strongly required that fulfill real-time requirements. In this paper we present the video encryption algorithm Puzzle to encrypting video streams in software. It is fast enough to fulfill real-time constraints and to provide a sufficient security. Puzzle is a video compression independent algorithm which can be easily incorporated into existing multimedia systems.

Secure and efficient key distribution for collaborative applications

Confidentiality is a key demand for many collaborative applications in the Internet, e.g. business meetings. In a more and more mobile society there is an increasing need of spontaneous meetings in ad hoc environments, often with changing partners. To assure confidentiality of such meetings the partners have to agree upon a common secret key for encrypting their communication. While centralized collaborative systems provide practicable solutions for this, it still represents a challenging task in decentralized systems using the peer-to-peer paradigm. In this paper we present a simple key distribution protocol, called VTKD, which was especially designed for small dynamic peer groups. It consists of two parts: a mutual authentication of the partners and a secure key renewal. The protocol uses a virtual token to determine the partner responsible for the key generation and distribution procedure. VTKD fulfills the relevant demands concerning group key exchange and is more efficient related to key renewal delay than existing key exchange protocols

Puzzle - an efficient, compression independent video encryption algorithm

Real-time video streams require an efficient encryption method to ensure their confidentiality. One of the major challenges in designing a video encryption algorithm is to encrypt the vast amount of video data in real-time to satisfy the stringent time requirements. Video encryption algorithms can be classified according to their association with video compression into joint compression and encryption algorithms and compression-independent encryption algorithms. The latter have a clear advantage over the former regarding the incorporation into existing multimedia systems due to their independence of the video compression. In this paper we present the compression-independent video encryption algorithm Puzzle, which was inspired by the children game jigsaw puzzle. It comprises two simple encryption operations with low computational complexity: puzzling and obscuring. The scheme thereby dramatically reduces the encryption overhead compared to conventional encryption algorithms, such as AES, especially for high resolution video. Further outstanding features of Puzzle are a good trade-off between security demands and encryption efficiency, no impairment on video compression efficiency, and an easy integration into existing multimedia systems. This makes Puzzle particularly well-suited for these security-sensitive multimedia applications, such as videoconferencing, where maximal security and minimal encryption overhead are desired simultaneously.

A secure p2p video conference system for enterprise environments

Many emerging group oriented and collaborative applications such as audio/video conferences use the peer-to-peer (P2P) paradigm. Confidentiality is an often demanded feature for such applications, e.g. in business meetings, to provide group privacy. How to build a secure P2P video conference system is still an open issue. In this paper several possible solutions are discussed. We present a security architecture used for P2P video conferences that ensures confidential talks in an enterprise environment whose branches might be geographically dispersed.

A Simple Balanced Password-Authenticated Key Agreement Protocol

Password authentication protocols have been broadly deployed in client/server communication settings for its convenient usage and low costs of deployment. Nowadays peer-to-peer networks become increasingly popular, where the role of principals is symmetric (balanced), i.e. each principal acts not only as a client but also as a server. In this setting a robust and simple password authentication protocol is highly desired, since PKIs (Public Key Infrastructures) are not always available for authentication. In this paper, we present a simple password-authenticated key agreement protocol for the use in peer-to-peer communication paradigms. It fulfills the security requirements on password authentication protocols, and is resilient to passive and active attacks as well as dictionary attacks. The proposed scheme is more efficient than the well established protocols due to its simple design concept.

Security considerations on pervasive real-time collaboration

A real-time pervasive collaboration system enables people to work together on a certain task at anytime and from anyplace. Security is one of the primary concerns for these systems, when running over public networks. In particular, end-to-end security represents a crucial issue in pervasive collaboration environments due to the heterogeneity of the networks and devices used. In this paper, we explore the feasibility of security measures at the diverse protocol layers to shielding pervasive real-time collaboration systems, and propose a security framework residing at the application layer to secure pervasive collaborations.

Designing Security Architecture for a P2P Video Conference System

More and more modern group oriented collaborative applications use the peer-to-peer (P2P) paradigm to be independent of expensive infrastructures as they are, for instance, provided for audio and video conferences by H.323 systems. Decentralized collaborative P2P solutions require appropriate mechanisms to protect group privacy and data integrity. A centralized client/ server based video conference system can be well shielded in a standard manner, whilst there are no off-the-shelf approaches to securing a P2P video conference up to now. This paper addresses this urgent issue by presenting an effective and flexible security architecture and showing how it can be embedded into a P2P video conferencing system using the BRA VIS system [4] as an example.