Christian Buttstedt - Professional IT Services
 

Projects

 

Project:

Period: 05/2004 - 10/2004
 
Customers: Sun Microsystems GmbH, Telefonica GmbH in Verl
 
Project: Multi Portal to represent different business processes
(Project team with approx. 20 members)
 
Position: Software developer and subproject manager
 
Tasks: Design and implementation of multi-tier portal applications to represent business processes:
  • Analysis and specification of the business process to manage basic claims data of customers
  • Analysis and specification of the business processes to take and execute an order
  • Development of a technical concept and architectural design of the web frontend components
  • Composition of a site map
  • Development of Ant scripts to configure, assemble, build and deploy the complete portal application
  • Implementation of the frontend components (DTOs, Form Beans, Struts Actions, JSPs, validation)
  • Implementation of a data mapper to generate XML documents with JAXB
  • Implementation of the functionality to access the business tier (service locator, business delegates, business facade)
  • Coaching of project staff
  • Specification of the Release Engineering Process
  • Testing, debugging and bug fixing for the complete portal application
  • Analysis, estimation and implementation of change requests
 
Technical requirements: Programming languages:
  • Java 2 SDK 1.4.2
  • Unix Shell scripts
Technologies:
  • J2EE 1.4
  • Java Architecture for XML Binding (JAXB) 1.0
  • Java Server Pages JSP 1.2
  • Java Servlet Specification 2.3
  • Tag Libs 1.0
  • EJB 2.0
  • XHTML 1.0 Transitional
Frameworks and toolkits:
  • Apache Jakarta Struts 1.1
  • Apache Jakarta Ant 1.4.1
  • Apache Jakarta Log4j
Products:
  • Sun ONE Application Server 7.0
  • Sun Java System Message Queue 3.5
  • Oracle 9i
  • DbVisualizer 4.0.4
  • Sun ONE Studio 5 Enterprise Edition
  • CVS
  • Oxygen XML Editor 4.0
Operating systems:
  • Sun Solaris 5.9 (test and operation platform)
  • Suse Linux 8.x (development platform)
 

Project:

Period: 08/2003 - 04/2004
 
Customers: Antal Ltd., Accenture AG, Bundesagentur für Arbeit in Nürnberg
 
Project: Virtueller Arbeitsmarkt (VAM): Internet portal and intranet applications which provide an online job search engine of the Bundesagentur für Arbeit
(Project team with approx. 100 members)
 
Position: Software developer and technical consultant
 
Tasks: Development of three subsystems for the portal on the basis of the MVC (Model-View-Controller) design pattern. Participation in the development phases analysis, design, implementation and test:
  • Analysis and specification of the site map
  • Development of layout presentations using XHTML and CSS
  • Evaluation of framework components for pagination, form validation and navigation
  • Review of the technical concept
  • Review of the software design: presentation view (HTML, TagLibs, JSPs), presentation control (servlets, conversations), service (stateless session beans), business logic (entity beans CMP), data access (JDBC, SQL)
  • Implementation of a subsystem to create and manage resubmissions for staff members of the Bundesagentur für Arbeit
  • Implementation of a subsystem to manage documents for users of the portal (e.g. upload and opening of PDF documents)
  • Implementation of a subsystem to represent a list of questions and to gather health information which is relevant for the placement service
  • Processing of functional module tests for the frontend components (manually with check list) and backend components (automatically with JUnit)
  • Processing of overall integration tests followed by debugging and bug fixing
  • Analysis, estimation and implementation of change requests
  • Examination and implementation of a web design in accordance with the ordinance of Barrier-Free Information Technology (BITV)
  • Analysis, implementation and test of the authorisation concept on application level
  • Enhancement of the pagination framework
  • Preparation of the functional acceptance test
 
Technical requirements: Programming languages:
  • Java SDK 1.3.1
  • Unix Shell scripts
Technologies:
  • J2EE 1.3
  • Java Server Pages JSP 1.2
  • Java Servlet Specification 2.3
  • Tag Libs 1.0
  • EJB 2.0
  • XHTML 1.0 Transitional
Frameworks and toolkits:
  • General and Reusable Netcentric Delivery Solution (GRNDS) 3.3 (Portal framework of Accenture which is comparable to Struts)
  • Apache Jakarta Ant 1.4.1
  • JUnit
Products:
  • BEA WebLogic Server 7.0
  • Sun ONE Webserver 6.0
  • Sun ONE Directory Server 5.1
  • Oracle 9i Net Services Release 2
  • DbVisualizer 2.1 bzw. 4.0.2
  • JBuilder 7.0
  • Eclipse 2.1.2
  • WinCVS 1.3
Operating systems:
  • HP-UX 11 (test and operation platform)
  • Windows 2000 Professional (development platform)
 

Project:

Period: 07/2001 - 06/2002
 
Customers: Sun Microsystems GmbH, Eplus Mobilfunk GmbH in Düsseldorf
 
Project: iMode/i-mode - Mobile Internet Portal
(Project team with approx. 40 members)
 
Position: Software developer and technical consultant
 
Tasks: Design of the architecture and implementation of the connectivity between the iMode portal and the backend systems. Support of the operating team to launch the service:
  • Technical analysis and specification of the interface between Portal Manager and Elink system
  • J2EE design and implementation of the business tier to connect the application server with a directory server (LDAP) and a Tuxedo server (stateless session beans, data access objects, value objects)
  • Installation and configuration of the iPlanet and Bea products (see below) on the development and testing platforms
  • Development and processing of test cases to check the connectivity between the Portal Manager and the Elink system
  • Technical documentation referring to the installation and configuration of the Tuxedo connector
  • Enhancement and adaption of Ant and Shell scripts for the configuration, assembling, build and deployment of the portal releases
  • Debugging and bug fixing for the testing and operating platform
  • Analysis of log files and performance tuning of the iPlanet Application Server 6.0 on the production system
  • Coaching and support of the operating team for the Portal Manager and the iPlanet products
 
Technical requirements: Programming languages:
  • Java SDK 1.2.2, 1.3.1
  • Unix Shell scripts
Technologies:
  • J2EE (Servlets, JSP, Tag Libs, EJB, RMI, JDBC)
  • iMode/i-mode ihtml
  • XML
  • Java Architecture for XML Binding (JAXB) 1.0
  • Netscape LDAP SDK 4.18
Frameworks and toolkits:
  • Apache Jakarta Struts Framework 1.0
  • Apache Jakarta Log4j 1.1.3
  • Apache Jakarta Ant 1.4
  • JUnit 3.7
Products:
  • iPlanet Application Server 6.0
  • iPlanet Unified Integration Framework 6.0
  • iPlanet Enterprise Connector for Tuxedo 6.0
  • iPlanet Web Server 6.0
  • Netscape Directory Server 4.x
  • Bea Elink
  • Bea Tuxedo Server 6.5
  • Bea Tuxedo Workstation Client 6.5
  • Oracle Client 8.1.7
  • Forte 3.0
  • Together 5.0
  • CVS
  • Bugzilla 2.14
Operating systems:
  • Sun Solaris 8 (test and operation platform)
  • Windows 2000 Professional (development platform)
 

Project:

Period: 04/2000 - 04/2001
 
Customers: Sun Microsystems GmbH, Eplus Mobilfunk GmbH in Düsseldorf
 
Project: EOL - Portal service for customers (providing user management, personalization, security and content management for Web and WAP devices)
(Project team with approx. 30 members)
 
Position: Software developer and technical consultant
 
Tasks: Customization and enhancement of the iPlanet Portal Application Framework (PAF) to match special requirements of Eplus:
  • Evaluation of different APIs to use SSL with Java
  • Enhancement of the PAF backend to fetch encrypted content from content providers (SSL via HTTPS)
  • Design of a Document Type Definition (DTD) for portal content and implementation of a XML parser
  • Implementation of CMS functions to store portal content
  • Debugging and bug fixing for the complete portal application
  • Installation and configuration of the Netscape Application Server as a scaleable and highly available cluster (load balancing)
  • Coaching and support of the operating team
  • Technical documentation for PAF
 
Technical requirements: Programming languages:
  • Java SDK 1.2.1
Technologies:
  • J2EE (Servlets, JSP, JDBC)
  • XML
Frameworks and toolkits:
  • iPlanet Portal Application Framework (PAF)
Products:
  • Netscape Application Server 4.0
  • Netscape Directory Server 4.x
  • Netscape Enterprise Server 3.x, 4.x
  • Oracle Client 8.0.5
  • Visual Cafe
  • CVS
  • Bugzilla 2.11
Operating systems:
  • Sun Solaris 2.6 (test and operation platform)
  • Windows 2000 Professional (development platform)
 

Project:

Period: 02/2000 - 03/2000
 
Customer: Beta Research GmbH in Unterföhring
 
Project: Playout Scheduling System - Time-dependent sequential control of a broadcast channel
(Project team with approx. 5 members)
 
Position: Software developer
 
Tasks: Analysis and development of a concept to test modules of the Playout Scheduling System:
  • Evaluation of different testing frameworks
  • Development of a testing concept and abstract formulation of test cases
  • Development of shell scripts to automatically generate the test classes in C++
 
Technical requirements: Programming languages:
  • C++
  • Shell scripts
Frameworks and toolkits:
  • CppUnit 3.0
  • Unix-Tools (awk, sed)
Products:
  • C++Builder
Operating systems:
  • Sun Solaris 2.6 (test and operation platform)
  • Windows NT 4.0 (development platform)
 

Project:

Period: 01/2000
 
Customer: SME AG in Garching
 
Project: Application for an extranet
(Project team with approx. 5 members)
 
Position: Software developer
 
Tasks:
  • Design and implementation of a virtual notice board for external working staff
  • Setting up the access by a web browser via the HTTP protocol
  • Dynamically generated web content Java Servlets and HTML
 
Technical requirements: Programming languages:
  • Java SDK 1.2.1
Technologies:
  • Java Servlets
  • HTML
Operating systems:
  • Windows NT 4.0
 

Project:

Period: 09/1998 - 10/1998
 
Customer: Munich Re Group in Munich
 
Project: Software development for the actuarial department HUK/Vertrag
(Project team with approx. 5 members)
 
Position: Mathematician and software developer
 
Tasks:
  • Design of an API (C++) for mathematical modelling of special distributions according to risk theory
  • Integration of algorithms in the scope of the diploma thesis "Distribution dependent procedures to approximate aggregate loss" into an existing API (C++)
  • Implementation of classes for affin linear transformations of distributions and for the empirical distribution
 
Technical requirements: Programming languages:
  • MS-Visual C++
Technologies:
  • MFC
Operating systems:
  • Windows NT
 

Project:

Period: 11/1997 - 08/1998
 
Customer: Munich Re Group in Munich
 
Project: Diploma thesis "Distribution dependent procedures to approximate aggregate loss"
(Project team with approx. 3 members)
 
Position: Mathematician and software developer
 
Tasks:
  • Mathematical modelling of the aggregate loss of a portfolio using the collective model of risk theory to calculate the aggregate loss distribution
  • Use of different techniques for discretisation of the distribution of claim severity
  • Analysis of the recursive procedures of Panjer and the Fast-Fourier procedure to approximate the aggregate loss distribution
  • Implementation of all algorithms in order to analyse performance and accuracy by a computer program
 
Technical requirements: Programming languages:
  • C++
Frameworks and toolkits:
  • GNU Make, UNIX-Tools
Operating systems:
  • Windows NT
  • Suse Linux 5.0
 

Project:

Period: 03/1997 - 04/1997
 
Customer: Munich Re Group in Munich
 
Project: Software development for the actuarial department HUK/Vertrag
(Project team with approx. 5 members)
 
Position: Mathematician and software developer
 
Tasks:
  • Development of an interface of DLL functions to use mathematical functions (written in C) in EXCEL
  • Implementation of different statistical distribution classes, a method for discretisation of continuous distributions and the Panjer algorithm to calculate the aggregate loss distribution for an API (C++)
 
Technical requirements: Programming languages:
  • MS-Visual C++
Technologies:
  • MFC
Frameworks and toolkits:
  • GNU Make, UNIX-Tools
Products:
  • EXCEL
Operating systems:
  • Windows NT
 

Project:

Zeitraum: 03/1996 - 04/1996 und 09/1996 - 10/1996
 
Customer: Universität der Bundeswehr in Munich
 
Project: Software development for the faculty of Aerospace Technology
(Project team with approx. 10 members)
 
Position: Software developer
 
Tasks:
  • Improvement of a supporting system for pilots, which is tested in a flight simulator
  • Development of an object-oriented API to control a multi-function display
  • Design criteria are modularity, reliability and simple utilization by the user
  • Adapting of existing software modules to this API
 
Technical requirements: Programming languages:
  • C++
Frameworks and toolkits:
  • GNU Make, UNIX-Tools
Operating systems:
  • IRIX Unix