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Writing World-Wide Web CGI scripts in the REXX language

Description: This talk is aimed at people who have experience with REXX and are interested in using it to write WWW CGI scripts. As part of this, the author describes several functions that are available in a library of REXX functions that simplify writing WWW CGI scripts. This library is freely available at //www.slac.standard.edu/slac/www/tool/cgi-rexx/.
Date: March 1, 1996
Creator: Cottrell, R.L.A.
Partner: UNT Libraries Government Documents Department

ATROPOS: a versatile data acquisition and analysis system

Description: Versatile, portable, rugged, and compact test and control modules for use in the development and testing of detection equipment for high-energy physics experiments are frequently needed at SLAC. The basic system developed is based on an LSI-11 microcomputer with 24K RAM, 4K ROM, 2 serial interfaces (one to the console terminal, the other to the large SLAC IBM computer complex (the TRIPLEX)), a programable clock, and a CAMAC crate controller. Data logging support is provided for magnetic tape, floppy disk, and an interactive program (ACQUIRE) which runs on the TRIPLEX under the timesharing system ORVYL. Data are read from various CAMAC modules, collected, buffered, and optionally logged. At a lower priority, the data read are sampled and analyzed in real-time on the LSI-11 to produce various histograms and tables. Concurrently, a more extensive analysis can be performed by the TRIPLEX program on the data which are logged to it. Interactive facilities provided by the microcomputer operating system enable the user to change CAMAC module addresses and the function codes used with them, specify various data cuts and transformations that are to be performed on the sample data, and specify new histogram limits and titles. Results of the real-time analysis, by both the microcomputer and the TRIPLEX program (if it is attached), may be displayed in graphical or tabular form on the console terminal. The basic system hardware cost (exclusive of the magnetic tape drive and floppy disk drive) is around $7000. The software is written in a modular fashion so that the user can supply his own data reading and analysis routines. This system has been in use for two years by various groups on several LSI-11s at SLAC. 3 figures.
Date: October 1, 1978
Creator: Logg, C.A. & Cottrell, R.L.A.
Partner: UNT Libraries Government Documents Department

Simulation of LSI-11/PDP-11 series minicomputers. [Runs on IBM 370]

Description: A functional simulation of te PDP-11 series minicomputers was implemented to run either interactively or as a batch job on an IBM 370 computer. The simulator operates in two modes, the supervisor mode and the run mode. In the supervisor mode, the simulator implements a command language, which allows users to examine and change the contents of memory or other addressable registers in the simulated machine. Optionally, an instruction trace may also be turned on or off. In the run mode, the simulation of the instruction set is tested by successfully running DEC's MAINDEC basic instruction test on the simulated machine. The interrupt structure is modeled. The simulation is open ended in the sense that users may define new peripheral devices, by including their own FORTRAN callable subroutines for each simulated device. Currently the following devices are supported: floppy disks, a console terminal, a card reader, a card punch, a line printer, and a communications multiplexer (DH11). With these devices DEC's RT-11 versions 2C and 3B have been successfully run on the simulator. At SLAC this simulator is proving useful in debugging software for one-of-a-kind hardware configurations, such as communications front end processors, that are not readily accessible for stand alone testing. 5 figures.
Date: April 1, 1979
Creator: Myers, J.R.; Cottrell, R.L.A. & Bricaud, B.M.
Partner: UNT Libraries Government Documents Department

Distributed computing environment monitoring and user expectations

Description: This paper discusses the growing needs for distributed system monitoring and compares it to current practices. It then goes on to identify the components of distributed system monitoring and shows how they are implemented and successfully used at one site today to address the Local Area Network (LAN), network services and applications, the Wide Area Network (WAN), and host monitoring. It shows how this monitoring can be used to develop realistic service level expectations and also identifies the costs. Finally, the paper briefly discusses the future challenges in network monitoring.
Date: November 1, 1995
Creator: Cottrell, R.L.A. & Logg, C.A.
Partner: UNT Libraries Government Documents Department

Network resource and applications management at SLAC

Description: The Stanford Linear Accelerator Center (SLAC) has a heterogeneous networked computing environment with a variety of transmission media, protocols, equipment from multiple vendors, Local Areas Network (LAN) and Wide Area Network (WAN) connections, workstations, servers, legacy mainframes, operating systems, network services and applications, and users of various skill levels. New technologies are continually being deployed as they become available. All of these components work together (most of the time) but result in a complex distributed computing environment (henceforth referred to as the system) which requires automated monitoring and management for the maintenance of high quality performance with limited personnel and budgets. There is no Network Management Station (NMS) product which comes close to doing the job of monitoring and managing the LAN and WAN for SLAC. However, by making use of Ping, Simple Network Management Protocol (SNMP) and its Management Information Bases (MIBs), as well as network applications (trace-route, File Transfer Protocol (FTP), Remote Procedure Calls (RPCs), Remote Shell (rsh), et.al.), an NMS (Netview for AIX), and the accounting and monitoring facilities provided by the server operating systems, the challenge is surmountable.
Date: February 1, 1996
Creator: Logg, C.A. & Cottrell, R.L.A.
Partner: UNT Libraries Government Documents Department

Network management and performance monitoring at SLAC

Description: The physical network plant and everything attached to it, including the software running on ``computers`` and other peripheral devices is the {bold system}. Subjectively, the ultimate measurers of {bold system} performance are the users and their perceptions of the performance of their networked applications. The performance of a {bold system} is affected by the physical network plant (routers, bridges, hubs, etc.) as well as by every ``computer`` and peripheral device that is attached to it, and the software running on the computers and devices. Performance monitoring of a network must therefore include computer systems and services monitoring as well as monitoring of the physical network plant. This paper will describe how this challenge has been tackled at SLAC, and how, via the World Wide Web, this information is made available for quick perusal by concerned personnel and users.
Date: August 1, 1995
Creator: Logg, C.A. & Cottrell, R.L.A.
Partner: UNT Libraries Government Documents Department

Network management, status and directions

Description: It has been said that the network is the system''. This implies providing levels of service, reliability, predictability and availability that are commensurate with or better than those that individual computers provide today. To provide this requires integrated network management for interconnected networks of heterogeneous devices covering both the local campus and across the world and spanning many administrative domains. This talk will review the status of existing tools to address management for networks. It draws on experience from both within and outside the HEP community.
Date: September 1, 1992
Creator: Cottrell, R.L.A. & Streater, T.C.
Partner: UNT Libraries Government Documents Department

Scientific Measure of Africa's Connectivity

Description: Data on Internet performance and the analysis of its trend can be useful for decision makers and scientists alike. Such performance measurements are possible using the PingER methodology. We use the data thus obtained to quantify the difference in performance between developed and developing countries, sometimes referred to as the Digital Divide. Motivated by the recent interest of G8 countries in African development, we particularly focus on the African countries.
Date: April 24, 2006
Creator: Zennaro, M.; Canessa, E.; Sreenivasan, K. R.; Rehmatullah, A. A. & Cottrell, R. L.
Partner: UNT Libraries Government Documents Department

What is the Internet doing for and to you?

Description: Many HEP sites have been participating in a project to monitor end-to-end Internet performance. A few sites have acted as central collection, analysis and report generation points for the large amount of data generated. The reports are useful for short term trouble identification, long term projections, and the evaluation of Internet services. The work is illustrated by examples of both detailed and more general Internet performance.
Date: June 1, 1997
Creator: Cottrell, R.L.A.; Logg, C.A. & Martin, D.E.
Partner: UNT Libraries Government Documents Department

eGY-Africa: Addressing the Digital Divide for Science in Africa

Description: Adoption of information and communication technologies and access to the Internet is expanding in Africa, but because of the rapid growth elsewhere, a Digital Divide between Africa and the rest of the world exists, and the gap is growing. In many sub-Saharan African countries, education and research sector suffers some of the worst deficiencies in access to the Internet, despite progress in development of NRENs - National Research and Education (cyber) Networks. By contrast, it is widely acknowledged in policy statements from the African Union, the UN, and others that strength in this very sector provides the key to meeting and sustaining Millennium Development Goals. Developed countries with effective cyber-capabilities proclaim the benefits to rich and poor alike arising from the Information Revolution. This is but a dream for many scientists in African institutions. As the world of science becomes increasingly Internet-dependent, so they become increasingly isolated. eGY-Africa is a bottom-up initiative by African scientists and their collaborators to try to reduce this Digital Divide by a campaign of advocacy for better institutional facilities. Four approaches are being taken. The present status of Internet services, problems, and plans are being mapped via a combination of direct measurement of Internet performance (the PingER Project) and a questionnaire-based survey. Information is being gathered on policy statements and initiatives aimed at reducing the Digital Divide, which can be used for arguing the case for better Internet facilities. Groups of concerned scientists are being formed at the national, regional levels in Africa, building on existing networks as much as possible. Opinion in the international science community is being mobilized. Finally, and perhaps most important of all, eGY-Africa is seeking to engage with the many other programs, initiatives, and bodies that share the goal of reducing the Digital Divide - either as a direct policy ...
Date: June 16, 2010
Creator: Barton, C. E.; Amory-Mazaudier, C.; Barry, B.; Chukwuma; Cottrell, R. L.; Kalim, U. et al.
Partner: UNT Libraries Government Documents Department