Thomas Eirich

Secure password-based cipher suite for TLS

SSL is the de facto standard today for securing end-to-end transport on the Internet. While the protocol itself seems rather secure, there are a number of risks that lurk in its use, for example, in web banking. However, the adoption of password-based key-exchange protocols can overcome some of these problems. We propose the integration of such a protocol (DH-EKE) in the TLS protocol, the standardization of SSL by IETF. The resulting protocol provides secure mutual authentication and key establishment over an insecure channel. It does not have to resort to a PKI or keys and certificates stored on the users computer. Additionally, its integration in TLS is as minimal and non-intrusive as possible.

JavaCard-from hype to reality

In this final of three related articles about smart card technology, the authors discuss the JavaCard, a much-hyped technology that is finally taking off as a multiapplication smart card. The main reason for the hype is JavaCards potential. Not only would it let all Java programmers develop smart card code, but such code could be downloaded to cards that have already been issued to customers.

Mote Runner: A Multi-language Virtual Machine for Small Embedded Devices

This paper introduces a new virtual machine for sensor networks and small embedded devices which has been designed with efficient resource usage and an event-driven programming model in mind. The virtual machine runs on 8, 16, and 32-bit micro-controllers with as little as 4KBof volatile and 32 KB of non-volatile memory. Our virtual machine is not bound to a single high-level programming language, but targets all strictly-typed programming languages.In conjunction with the virtual machine, we also present our development tool chain for Java and C#, and discuss the effects of our virtual machine design on these high-level languages. We also present a compact load-file format which allows applications to be stream-linked in a way that minimizes memory usage and bandwidth. All presented components are part of the IBM Mote Runner, a run-time environment for wireless sensor networks.

Energy-efficiency through micro-managing communication and optimizing sleep

Energy-efficiency is key to meet lifetime requirements of Wireless Sensor Networks (WSN) applications. Todays run-time platforms and development environments leave it to the application developer to manage power consumption. For best results, the characteristics of the individual hardware platforms must be well understood and minutely directed. An Operating System (OS) with suitable programming abstractions can micro-manage power consumption of resources. We demonstrate with the Mote Runner platform how the inherent overhead of managed application code is compensated for by a platform-independent communication API together with sleep optimizations. The proposed abstractions and optimizations can be applied to other modern sensor network platforms. To quantify the effectiveness of our approach, we measured the energy efficiency of a real-world WSN application using a custom TDMA communication protocol fully implemented on both Mote Runner and TinyOS. Mote Runners power management and sleep phase optimizations outperforms TinyOS in our test application for duty cycles below 10% on the Iris hardware.