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A data sharing middleware for ad-hoc networks


Latest updates:

May 2004 XMIDDLE software and project moved to sourceforge.


XMIDDLE is a collaborative effort by the Department of Computer Science of University College London to design and implement a middleware that will adhere to the needs of application developers that target mobile devices.

In recent years, we have seen a proliferation of mobile devices, such as PDAs, mobile phones, and laptops. These devices are getting increasingly more powerful from a computational point of view, and are also acquiring wireless network connectivity in the form of IrDA, Bluetooth, 802.11b, etc. 

These technologies, allow a large body of interesting applications to be created targeting these platforms, exploiting their capability to form ad-hoc peer to peer networks. However, they also present a number of new challenges to the mobile application developer. Compared to traditional distributed systems, these systems suffer from a low bandwidth and non-continuous network connection, limited resources (such as memory and processing power), limited battery life, and the inability to always access information located on a specific host remotely.

Traditionally, middleware systems have been used to address the needs of application developers targeting distributed systems. However, we have found that such systems are either too heavyweight to be applied to mobile hosts, or are not powerful and flexible enough to address the requirements of such systems.

With this in mind, we have designed and implemented XMIDDLE, a data-sharing middleware for mobile computing. XMIDDLE allows applications to share data that are encoded as XML with other hosts, to have complete access to the shared data when disconnected from the network, and to reconcile any changes made with all the hosts sharing the data when possible. The goal is to make sure that eventually all hosts will have a consistent version of the shared data. XMIDDLE is very lightweight and fast, and caters for the frequent disconnection behaviour that mobile devices exhibit. XMIDDLE also allows applications to influence the reconciliation process as to how to resolve conflicts.



Last update: May 2004 by Stefanos Zachariadis