Nader Mazen Rabadi

Privacy Protection Among Drivers in Vehicle-to-Vehicle Communication Networks

The privacy of future drivers will dispute with the evolvement of vehicle-to-vehicle (V2V) communication networks. V2V networks are a subclass of mobile ad hoc networks (MANET). Future vehicles will collaborate for safe and efficient driving using wireless communications. Vehicles will exchange safety-critical information without a control from a centralized basestation or infrastructure. However, a centralized infrastructure, presented as a management entity or a certificate authority (CA), is necessary to establish and provide trust and secure communication protocols among drivers. This can be achieved using the public key infrastructure (PKI) and digital certificates. The CA provides a unique certificate for each driver. The disadvantage of unique certificates is that the identity of drivers can be revealed to other drivers, and the movements and locations the drivers visit can also be traced by other drivers. In this paper, we present an approach to provide privacy among drivers in V2V communication networks. Our approach is based on the concept of group signatures. Drivers, who are members of V2V networks, are organized into groups. Each group has a public key. Members of a group share their groups public key. In addition, each member has its own private key provided by the CA. In our proposed solution, we achieve privacy by allowing members to generate and change their own set of public keys frequently using the Digital Signature Standard (DSS). In our approach the CA is not required to authenticate the frequently generated public keys, and hence vehicles exchange the safety- critical information without requiring a control from the CA. When a group member changes its own public keys, it is hard to trace the movements and locations that member visits. A group member signs messages using the shared group public key, its own private key, and its own frequently-changed public keys. The recipients of a signed message can verify the correctness of the signature without identifying the signer. In case of a dispute and malicious activities, the identity of the member who signed the disputed message can be revealed only by the CA.

Performance Evaluation of IEEE 802.11a MAC Protocol for Vehicle Intersection Collision Avoidance System

Vehicle-to-vehicle (V2V) communications network is a subclass of mobile ad hoc networks (MANET). With the new dedicated short range communications (DSRC) at 5.9 GHz, vehicles equipped with DSRC devices will communicate and collaborate to broadcast their safety-critical information to each other. DSRC is to be used in a wide range of advanced vehicle safety applications such as intersection collision avoidance system. The DSRC specification is based on the physical (PHY) and medium access control (MAC) layers of the IEEE 802.11a. The MAC mechanism for the IEEE 802.11a is the distributed coordination function (DCF), which is based on carrier sense multiple access with collision avoidance (CSMA/CA). Mobile nodes contend for the channel using a DCF random backoff timer. A random backoff algorithm chooses a Contention Window (CW) value between aCWmin and aCWmax. The random number, CW, is the number of time slots the mobile node has to sense the channel idle before it may transmit. In this paper, we developed an intersection traffic simulator to evaluate the settings of IEEE 802.11a DCF aCWmax on the available bandwidth per vehicle and on the required communication range. Our simulation results show that it is sufficient to set the aCWmax to 200 and the communication range to 200m for the intersection collision avoidance system enabled by DSRC.

Anonymous Group Implicit Certificate Scheme

We propose an anonymous identity-based public key group implicit certificate scheme to preserve the anonymity of mobile users in a communication network. The use of a standard public key certificate in a wireless communication network will allow unauthorized entities, who are listening to the communication channel, to identify and trace movements and locations of a mobile user using the users unique public key in the certificate. The disclosure of such information may raise privacy concerns. In our proposed anonymous identity-based public key group implicit certificate scheme, recipients of a broadcasted message can authenticate the transmitter and validate the integrity of the message without identifying the transmitter. In case of a dispute and malicious activities, the identity of the mobile user who broadcasted the disputed message can be revealed only by a trusted authority.

Decentralized secure protocol for inter-vehicle communication networks

In this paper, we propose a secure protocol for intervehicle communication (IVC) networks without the use of centralized roadside infrastructure. Future vehicles may use wireless IVC networks to exchange safety-critical information among each other. IVC networks do not have a centralized control, and instead rely on vehicles to coordinate with each other to exchange information. Because of the open medium, security is a concern in IVC networks. Vehicles need a mechanism to authenticate the safety-critical information that will be exchanged in IVC networks. A trusted third party Certificate Authority (CA) can provide such a mechanism through public-key certificates. However, the disadvantage of using public-key certificates is that drivers can identify each other. The certificate will allow privacy concern. In this paper, we propose to use RSA public key algorithm and Digital Signature Algorithm (DSA) to solve the security and privacy concerns in IVC networks. The paper presents a detailed description of our protocol, and shows its performance analysis in terms of processing times.

Channel Access Priority for Vehicle Intersection Collision Warning

We propose an intersection warning channel access priority (IWCAP) protocol to warn drivers of a possible collision when approaching an intersection. Our protocol operates via inter-vehicle communication (IVC) networks with one omni directional antenna per vehicle and one dedicated short range communication (DSRC) channel. The advantage of our protocol is that it can be used as an optional add-on medium access mechanism to the IEEE 802.11a MAC protocol. We describe in details the operation of our protocol and show the performance analysis in terms of latency, bandwidth, the required communication range and the required distance to an intersection to avoid a collision.