Towards a canonical software architecture for multi-device WebLabs

Traditionally the focus on WebLab design has been placed on the hardware side, i.e. enabling data and program transfer between a PC remotely accessible through TCP/IP and its attached controllable/programmable device. Little attention has been paid to the other communication segment going from the controlling PC (WebLab server) and the remote users' PCs, since this has been regarded as a "solved software problem". Consequently, aspects such as security, scalability, accessibility, user friendliness, or the possibility of collaborative work in WebLabs have often been disregarded. This situation may be resolved if a serious effort is placed on the definition of a proper distributed software architecture for WebLabs. In this paper, we describe such ideal software architecture, resulted from an iterative process seeking a Web-based, secure, scalable, multiuser, multi-device WebLab.

I. Introduction

The concept of WebLab has been around since the early nineties. Its development is widespread in laboratories of analog [1] and digital [2] electronics, programmable logic [3] or process control [4]. We can encounter good examples of WebLabs in different countries: USA [5], Colombia [6], Spain [3], [7], Portugal [8], Italy [9], Corea [4] and so forth.