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1. ABng poller & Linux Piccolo
Linux Piccolo is how we called a compact version of the
Linux operating system used in the ABng project. The system itself
is very small - just 12MB of hard disk space. Although small, the
system is quite
powerful. It enables the execution of CORBA based multithreaded
applications.
Our article on Linux Piccolo has been published in October issue #54 of Linux Journal. HTML version of the article is available here. The hardware on which the system runs is Intel based PC/104 single board computer with onboard Ethernet Interface. The dimensions of the PC are: (95mm x 150mm x 140mm), which makes Linux Piccolo one of the most compact Internet enabled UNIX servers. System does not require hard disk or the display adapter. It is controlled through the network.
2. abngpoller applicationabngpoller is a multi-threaded Linux application, with the main purpose of collecting sightings from the serial lines and distributing the received data to registered observers. This application can be configured to interface with sensors designed by the ORL as well as with the modified sensors commercially available from Olivetti. The six serial lines available in the prototype ABng poller can serve up to about 80 sensors with reasonable response time. When more sensors are needed, additional pollers must be deployed. The design of the ABng system places no limitation on the number of pollers; thus, system scalability is ensured.ABng poller is able to interact with the other parts of the system via the standard socket services or through the CORBA interface. This feature enables a smooth transition from the old ANSAWare-based location system to the CORBA-based ABng. Object Request Broker functionality is ensured by the omniORB which, although free, has performance levels hard to beat by the commercially available CORBA-compliant products including the industry leader--Orbix. An important feature of omniORB is its portability; it runs on most modern operating systems, including Linux. 3. LCD console
For the purpose of the initial network parameters configuration, ABng poller comes with the LCD console. A small 8-key keyboard allows the administrator to specify IP address and network mask for the computer. It is also possible to check interactively a predefined number of system parameters like number of serial networks connected to the system or number of sensors.
ABng console communicates with the host computer via RS-232 interface. For the exchange of data between host and a console, a simple protocol has been designed and implemented. Instead of hard-coding the console logic into the micro-controller a configuration file is used to specify prompts and actions. This approach allows execution of an arbitrary UNIX command from the console, with the output of the command displayed back on the console.
4. Webadmin module for ABng poller
LCD console is not the most convenient way to configure big number of parameters for the application like abngpoller. It allows however to specify the complete set of parameters required to configure TCP/IP stack and web server.
Any further configuration of the ABng poller can be performed via user-friendly graphical interface. User simply enters the address of the poller in the Web browser and the connection with Webadmin module running on ABng poller is established. From now on the parameters of the managed application can be easily adjusted. The Webadmin module is still under development. 5. Just a poller?As a result of ABng team's effort, a flexible and powerfull network computer has been created. With LinuxPiccolo as an operating system this computer takes advantage of huge amount of high quality software like Perl or Apache Web Server available for Linux. ABng poller is not just a platform to run abngpoller application on. It can be easily adapted to any appliaction. As a part of the ABng project an automated book library has been created. The main hardware component of this library is Abng poller connected to the bar-code scanner, runnig SQL database client and CORBA servers.Just like Corel NetWinder or Cobalt Cube, ABng poller is a robust and flexible network computer powered by Linux. |
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