Key establishment in sensor networks is a challenging problem because asymmetric key cryptosystems are unsuitable for use in resource constrained sensor nodes, and also because the nodes could be physically compromised by an adversary. We present three new mechanisms for key establishment using the framework of pre-distributing a random set of keys to each node. First, in the q-composite keys scheme, we trade off the unlikeliness of a large-scale network attack in order to significantly strengthen random key predistribution's strength against smaller-scale attacks. Second, in the multipath-reinforcement scheme, we show how to strengthen the security between any two nodes by leveraging the security of other links. Finally, we present the random-pairwise keys scheme, which perfectly preserves the secrecy of the rest of the network when any node is captured, and also enables node-to-node authentication and quorum-based revocation.

/pdf/random-key-predistribution-schemes-for-sensor-networks-2w3j5ne7ef.pdf

Random key predistribution schemes for sensor networks

The Elliptic Curve Digital Signature Algorithm (ECDSA) is the elliptic curve analogue of the Digital Signature Algorithm (DSA). It was accepted in 1999 as an ANSI standard and in 2000 as IEEE and NIST standards. It was also accepted in 1998 as an ISO standard and is under consideration for inclusion in some other ISO standards. Unlike the ordinary discrete logarithm problem and the integer factorization problem, no subexponential-time algorithm is known for the elliptic curve discrete logarithm problem. For this reason, the strength-per-key-bit is substantially greater in an algorithm that uses elliptic curves. This paper describes the ANSI X9.62 ECDSA, and discusses related security, implementation, and interoperability issues.

/pdf/the-elliptic-curve-digital-signature-algorithm-ecdsa-33tvnr4ena.pdf

The Elliptic Curve Digital Signature Algorithm (ECDSA)

An ad hoc network is a group of wireless mobile computers (or nodes), in which individual nodes cooperate by forwarding packets for each other to allow nodes to communicate beyond direct wireless transmission range. Prior research in ad hoc networking has generally studied the routing problem in a non-adversarial setting, assuming a trusted environment. In this paper, we present attacks against routing in ad hoc networks, and we present the design and performance evaluation of a new secure on-demand ad hoc network routing protocol, called Ariadne. Ariadne prevents attackers or compromised nodes from tampering with uncompromised routes consisting of uncompromised nodes, and also prevents a large number of types of Denial-of-Service attacks. In addition, Ariadne is efficient, using only highly efficient symmetric cryptographic primitives.

/pdf/ariadne-a-secure-on-demand-routing-protocol-for-ad-hoc-57ex02ywre.pdf

Ariadne: a secure on-demand routing protocol for ad hoc networks

As mobile ad hoc network applications are deployed, security emerges as a central requirement. In this paper, we introduce the wormhole attack, a severe attack in ad hoc networks that is particularly challenging to defend against. The wormhole attack is possible even if the attacker has not compromised any hosts, and even if all communication provides authenticity and confidentiality. In the wormhole attack, an attacker records packets (or bits) at one location in the network, tunnels them (possibly selectively) to another location, and retransmits them there into the network. The wormhole attack can form a serious threat in wireless networks, especially against many ad hoc network routing protocols and location-based wireless security systems. For example, most existing ad hoc network routing protocols, without some mechanism to defend against the wormhole attack, would be unable to find routes longer than one or two hops, severely disrupting communication. We present a new, general mechanism, called packet leashes, for detecting and thus defending against wormhole attacks, and we present a specific protocol, called TIK, that implements leashes.

/pdf/packet-leashes-a-defense-against-wormhole-attacks-in-38u1jm3yh9.pdf

Packet leashes: a defense against wormhole attacks in wireless networks

An ad hoc network is a group of wireless mobile computers (or nodes), in which individual nodes cooperate by forwarding packets for each other to allow nodes to communicate beyond direct wireless transmission range. Prior research in ad hoc networking has generally studied the routing problem in a non-adversarial setting, assuming a trusted environment. In this paper, we present attacks against routing in ad hoc networks, and we present the design and performance evaluation of a new secure on-demand ad hoc network routing protocol, called Ariadne. Ariadne prevents attackers or compromised nodes from tampering with uncompromised routes consisting of uncompromised nodes, and also prevents many types of Denial-of-Service attacks. In addition, Ariadne is efficient, using only highly efficient symmetric cryptographic primitives.

/pdf/ariadne-a-secure-on-demand-routing-protocol-for-ad-hoc-pug3drdfej.pdf

A method and system are provided for processing encrypted messages at a mobile device. A mobile device receives an encrypted message that comprises encrypted content as well as encryption information for accessing the encrypted content. At the mobile device, the encryption accessing information is obtained and stored to memory. The encription accessing information is retrieved from memory in order to decrypt the encrypted content when the encrypted message is subsequently accessed.

System and method for secure message key caching in a mobile communication device

The market for Personal Digital Assistants (PDAs) is growing at a rapid pace. An increasing number of products, such as the PalmPilot, are adding wireless communications capabilities. PDA users are now able to send and receive email just as they would from their networked desktop machines. Because of the inherent insecurity of wireless environments, a system is needed for secure email communications. The requirements for the security system will likely be influenced by the constraints of the PDA, including limited memory, limited processing power, limited bandwidth, and a limited user interface.

This paper describes our experience with porting PGP to the Research in Motion (RIM) two-way pager, and incorporating elliptic curve cryptography into PGP's suite of public-key ciphers. Our main conclusion is that PGP is a viable solution for providing secure and interoperable email communications between constrained wireless devices and desktop machines.

PGP in constrained wireless devices

Systems and methods of connection control for wireless mobile communication devices enabled for communication via a plurality of communication connections are provided. Connection control information associates software applications with communication connections. When a connection request specifying a requested connection is received from a software application, it is determined whether the requested connection is permitted by the connection control information. Where the requested connection is permitted by the connection control information, the requested connection is opened. If the requested connection is a first connection opened by the software application, then the software application is associated with the requested connection in the connection control information.

System and method of connection control for wireless mobile communication devices

A system and method of distributing authentication information for remotely accessing a computer resource. A request for authentication information, including identity information, is received from a user of a remote device. When the user is authenticated based on the identity information, requested authentication information is retrieved and returned to the remote device. The authentication information, or information generated from the authentication information, is then used for remotely accessing the computer resource.

System and method of secure authentication information distribution

Systems and methods of owner application control of an electronic device are provided. Owner application control information is stored on the electronic device and/or one or more remote servers. Owner application control information is consulted to determine if one or more required applications are available for execution on the electronic device. If not, one or more required applications not available are downloaded and installed. This could be in a manner transparent to the user of the electronic device. If one or more required applications are not available on the electronic device, the device can be functionally disabled in whole, or in part, until one or more required applications are available.

Michael G. Kirkup

Papers

System and method for secure message key caching in a mobile communication device

PGP in constrained wireless devices

System and method of connection control for wireless mobile communication devices

System and method of secure authentication information distribution

System and method of owner application control of electronic devices