Have you read the foreword/disclaimer to this CV?

Jos Visser

Tue Jan 21 16:26:05 CET 2003

This set of pages contains my curriculum vitae: a shameless display of my knowledge and skills. If you think this is way too much stuff to digest, why not download the 2 page ASCII text version? You can also download a PostScript or a PDF version of this CV.

Please note: This document is best experienced through the web. If you're reading the PostScript or PDF version, you still might want to surf to http://www.josvisser.nl/cv to experience the real thing complete with hyperlinks!

Alternatively, use this menu to jump immediately to the section of your preference:

  1. Some elementary details
  2. A really, really, quick introduction
  3. Everyone loves labels...
  4. Some of the stuff I know
  5. Some of the projects I recently did or was/am part of
  6. Teaching
  7. Presenting
  8. Writing
  9. Frequently Asked Questions

Some elementary details

Full name Josephus Cornelis Willibrordus Visser
... but just call me "Jos".
Date of birth 2 June 1966
Place of birth 's-Gravenhage
a.k.a. The Hague, in the Kingdom of the Netherlands
Languages Nederlands (vloeiend), English (fluently), Español (no malo), Deutsch (nicht slecht), Français (un peu).
E-mail josv@osp.nl
A picture of me
A picture of me. 
True, not the most flattering one but still accurate I'm afraid.
If you want even more pictures of me, follow this link.

A really, really, quick introduction

I have a B.Sc. (Ing.) in computer science from the The Hague polytechnic college (Dutch: Hogere Informatica Opleiding, HTS-I, graduated in 1988). In the last 15 years I've filled many different roles in large and small companies, as part of large and small projects. The common denominator of all my activities is a strong focus on operating systems, networks and other essential technical infrastructure. I am a quick thinker with both feet on the ground who can adjust rapidly to an existing situation, finding a pragmatic and working solution to a given predicament. My communicative skills (written and oral) are excellent. I enjoy teaching, giving presentations and writing articles. I have a gift for presenting difficult technical concepts in a clear and concise manner. Humour plays an important part in my life, and presumably the most honourable title I hold is that of the "InSANE Quiz Master". Until recently, I was a board member of the Dutch Unix User Group NLUUG.

Oh, and by the way, did I mention that I am very modest :-)

Everyone loves labels...

Things I am Things I am *not*
  • Unix/Linux specialist
  • Software developer (C, C++, Perl, Java)
  • Teacher
  • Writer
  • Four star diver
  • Wannabee improv actor
  • Wannabee standup comedian
  • Pragmatic
  • Independent
  • Self motivated
  • Outgoing

Some of the stuff I know

Computer platforms HP9000 workstations and servers, Sun workstations and servers (incl. Ultra 10,000), IBM RS/6000, Intel PC platforms, IBM S/390
Operating systems Unix various flavours (HP-UX, Linux, SunOS, Solaris, FreeBSD, Tru64, AIX), Windows NT, MVS (OS/390)
Programming languages C, C++, Java, shell script, Perl, JavaScript, plus a whole bunch of less topical ones such as Assembler (S/390, 80x86, 680x0, 6502, Z80), Forth, Lisp, Cobol, APL, Rexx, SAS, Prolog, CLIST, Basic, Caml/OCaml, Tcl/Tk, Comal
Software HP OpenView network node manager, HP Openview IT/Operations, Netscape Suitespot servers (Enterprise, Messaging, Certificate, Directory, Proxy, Calendar), Apache, OpenLDAP, OpenSSL, Sendmail, HP MC/ServiceGuard, Sun Enterprise Cluster (version 2 and 3), HP OmniBack II, Firewall-1, Veritas Volume Manager, Samba, MySQL, PostgreSQL, Veritas Netbackup, NCSA web server, CERN web server, Cisco IOS, IBM Websphere, IBM MQ Series, Tomcat, SilverStream, JBoss, PostgreSQL.
Technologies and protocols TCP/IP, SNMP, HTTP, SNMP, LDAP, NFS, Cryptography, X509, DNS/BIND, NIS, NIS+, DHCP, IMAP, POP3, OSPF, PPP, RIP, SMTP, CGI, CORBA, Motif, JSP/Servlets, NAT, firewalls, NFS, VPN, PKI, XML, DHTML, kernel internals, Posix, Ethernet, Token Ring, FDDI, OSI, SCSI, X-Windows, SAN
Interesting hardware EMC Symmetric disk arrays, Cisco routers, HP XP256/512 disk arrays
Java Sun Certified Developer for the Java Platform, Sun Java Server, J2EE, Enterprise Java Beans (EJB), JNI, RMI, JavaBeans JDBC JFC, JINI, JNDI, JSP, Swing
Mainframe stuff MVS (OS/390), JES2, Omegamon, SMP/E, Syncsort, VSAM, TSO, ISPF, DASD (3380, 3390), RACF, SNA, VTAM, JCL
  • Training
    • CBT/WBT/TBT Authoring and Production
    • Delivery with Classroom Instruction
    • Delivery with Distance Learning
    • Instructional Design
    • Program Management
    • Technical Course Development
  • Software development
    • Design Specifications
    • Functional Specifications
    • Technical Specifications
    • Code Debugging and Bug Fixing
    • Code Review and Checking
    • Programming Code to Specification
    • Requirements Definition
    • Software Architecture
    • Software Documentation
    • System Analysis
    • Systems Integration
    • Technical Writing
  • System management
    • Firewall Installation and Administration
    • Hardware Configuration
    • Job Scheduling
    • Kernel Development
    • Performance
    • Production Support
    • Security and User Administration
    • Security Intrusion Detection
    • Security Maintenance
    • Security Policies and Procedures
    • Security Testing and Auditing
    • Software Installation & Upgrade
    • Storage Management
    • Troubleshooting
  • Network management
    • Administration
    • Analysis
    • Architecture and Design
    • Configuration and Implementation
    • Connectivity Testing
    • Design
    • Diagnostics and Monitoring
    • Equipment Install and Configuration
    • Firewall Setup and Support
    • Management Tools
    • OS Installation and Upgrade
    • Performance Tuning
    • Protocols
    • Remote Access Services
    • Security
    • Standards & Procedures
    • Troubleshooting
  • Miscellanous
    • Web Performance Monitoring/Tuning
    • Lead Short Projects (1-3 Months)
    • Lead Small Teams (1-5)
    • Mentoring of Other Developers
    • Technology Strategic Planning
    • Proposal Writing
    • Sales Support
    • Security Risk Management

Some of the projects I recently did or am/was part of

Short Long
Secret :-) For a still secret .com venture I did the analysis, design (functional/technical) and software development of a completely web based enterprise. The software was completely developed in Java with technologies like Java Server Pages (Apache, Tomcat), XML/XSL (Xerces and Xalan), Enterprise Java Beans (entity and session beans), JBoss application server and PostgreSQL database.
Aldea Felina Completely irrelevant, but worth mentioning: I am a volunteer with the Aldea Felina cat shelter in Denia. There I do such worthy things as feeding cats, giving them medication and cleaning up their, hmmmm, refuge... For more information click here.
OpenComal I am the initiator of the OpenComal project. OpenComal is a free (open source) implementation of the Comal programming language. The OpenComal interpreter allows input, editing and execution of Comal programs.
ProxyTunnel I researched various technologies to break through firewalls and developed a program (ProxyTunnel, see here) that allows breaking through firewalls in order to establish arbitrary network connections.
Internet payment app For a large bank in the Netherlands, I was the technical guru in a team that strove to develop and deploy an Internet payment application for large corporate customers and financial institutions. My role focused on getting the app production ready and installable. I influenced coding standards (e.g. introduced Log4J), wrote critical parts of the application (e.g. performance plugins and a pooled multi threaded EJB connection pool to send messages from the front-end to the back-end), engineered the front-end app server environment (Apache/Tomcat), advised on security, built a deployment/build environment (based on CVS and Ant, generated HP-UX SD/UX install packages from the sources) and shot troubles. I was also part of a cross-country architecture team that strove to define the next generation web services architecture of the customer.
Java development For a large bank in the Netherlands, I have been doing some advanced Java development. Amongst the programs I wrote was a multithreaded broker that forwards messages from IBM MQ series queues into Enterprise Java Beans (EJBs) running under Websphere.
Infrastructure consultancy for .nl domain I advised the company that maintains the .nl Internet domain with regard to the infrastructure needed to run the domain registration systems.
HA Cluster for SoZaWe Rotterdam I have been working on converting two standalone systems into an HP-UX MC/ServiceGuard cluster. The primary reason for doing so is that the primary business application of the social services department of the city of Rotterdam must always be available, even in case one of the systems crashes or has to be brought down for maintenance purposes. The cluster runs an Oracle database and a standard application for keeping track of welfare recipients and payments.
Internet connection for major Dutch hospital I architected and implemented (together with a colleague) the Internet connection for a hospital in The Hague. The connection consists of a leased line which runs into a full DMZ built with Cisco routers, a Firewall-1 (on an HP9000) and a bunch of HP9000 A-series running services such as Netscape Proxy server, Sendmail relay (into an internal Netscape Messaging server), NNTP relay (into an internal Netscape Collabra server), DNS (with BIND obviously) and other gadgets.
Bank extranet I upgraded the extranet environment of a merchant bank in Amsterdam to the latest releases of Netscape Enterprise Server and WU-FTPD. As part of the upgrade I extended WU-FTPD with a feature for looking up users in an LDAP directory and wrote an NSAPI plug-in for the Netscape Enterprise Server to use the same LDAP directory server for some essential configuration information.
OmniBack-II I implemented HP OmniBack backup software at a hospital in the east of the Netherlands. Environment was an HP-UX MC/ServiceGuard cluster with two DLT2/20 tape libraries (2 drives and 20 slots in the library each) and integration with Oracle Enterprise Backup Utility (EBU) for online Oracle backups.
Directory services For a Dutch tax lawyer firm I reviewed their strategy to move to a central LDAP directory service through the use of a Meta-Directory. And, since I was there, I threw in some advice on how to improve the availability of their central Solaris infrastructure.
Internet connection for Dutch publisher For a Dutch publisher of educational books and methods I implemented and maintain (ongoing activity) their Internet connection. Environment is (and I'm not proud of that :-) Cisco routers, Windows NT server, Internet Information Server, MIME- and WebSweeper, BIND for Windows NT, Microsoft Proxy Server.
Openview Network Node Manager For a Dutch broad band Internet Provider I kicked off their use of HP OpenView Network Node Manager to monitor their network. A colleague of mine followed this up under my supervision.
Software port to HP-UX I provided some assistance to a large IT manufacturer to help port one of their applications from Digital Unix to HP-UX 11 & ANSI C++. Time was critical because the week thereafter the application was supposed to be installed at a major western intelligence service :-)
Java application architecture For a major Dutch player in the call centre business I was part of a project team to architect an important new component of their call centre software. The component was to be written in Java using advanced Java technologies such as Java Beans, Information Bus, JDBC, CORBA/RMI/DCOM et cetera. 
Software development: SRAM I am part of our core team that is responsible for architecting, developing and maintaining SRAM, the System Resource Availability Monitor (see http://www.osp.nl/sram). SRAM is used at a couple of major sites in the Netherlands to monitor processes and other important system resources. SRAM is developed in C++ and runs on all major versions of Unix.
IT/Operations implementations I was part of several projects that strove to automate Unix system operations by implementing HP/OpenView IT/Operations. As part of these projects I designed and wrote tons of shell scripts and C programs to check system status, report status to IT/O and perform call outs to pagers of stand-by operators.
E-Banking I was part of a major project at a Dutch bank that sought to reinvent its global business by making use of the Internet and browser technology. My role was that of "guru" on topics such as Internet protocols, cryptography, SSL, Unix and other deep core stuff.
Internet security penetration I performed an Internet security penetration test for a "high visibility" site of the Dutch government.
Computational cluster I implemented a HP9000 based computational cluster for a Dutch government office. Additionally I wrote software that distributed jobs across the cluster nodes (in combination with the since then discontinued HP TaskBroker software).
OS/390 Unix System Services I assisted a large Dutch bank in making the decision if and how to enable TCP/IP and Unix System Services on their IBM OS/390 mainframes. This was an interesting activity since it put most of my MVS and Unix+TCP/IP knowledge to the test.
SNA connectivity For the Dutch automobile club (ANWB) I configured SNA/3270 connectivity from an HP Unix cluster to their mainframe environment across a token ring that had a 3745 connected to it.

Please bear in mind that this is only a small excerpt. I did tons of other/smaller stuff which require deep hands-on knowledge of Unix and TCP/IP environments. Think about things like reorganizing disk mirroring and logical volume structures, configuring Sendmail to deliver mail to Microsoft Exchange, modifying a printer driver to disable the printer after 5 consecutive unsuccessful attempts and other interesting things.


I currently spent about 1/3 of my time teaching courses. Over the years, the list of stuff I taught about has grown large and impressive (I hope). The courses mentioned here were mostly conducted for training institutes such as these of Hewlett-Packard, Sun and Digital. Apart from these specific courses I used to teach Operating Systems in the 4th and 5th year of the The Hague polytechnic college (Dutch: HIO). Although I do not teach there anymore, I'm still involved, but now as one of the government appointed overseers (of the final exam).

The list of courses is pretty big. Most of these courses I've given multiple times to different audiences.  The titles usually speak for themselves.

Unix & networking courses

  • Unix fundamentals
  • HP-UX system administration
  • Solaris system and network administration
  • Digital Unix system administration
  • HP-UX network administration
  • Unix security
  • HP-UX performance and tuning
  • Solaris performance and tuning
  • HP-UX internals
  • Managing MC/ServiceGuard
    (HP-UX HA clustering)
  • Sun Enterprise Cluster
    (Solaris HA clustering, version 2 and 3)
  • Veritas Volume Manager
  • Managing Logical Volume Manager and MirrorDisk/UX
  • HP-UX administration for experienced administrators
  • Managing the X.25 connection
  • Managing LanManager/X
  • Administration of X-terminals
  • Introduction to X-Windows and HP VUE
  • Internet fundamentals
    A course I co-wrote with a collegue
  • Networking & Data communication fundamentals
  • Programming courses

  • Advanced shell script programming
  • Programming multi-threaded software in C
  • Perl Programming
  • Programming C
  • Programming C++
  • Programming X-Windows (XLIB)
  • Programming Java
  • Developing Java Beans/Component Based Development
  • Advanced Java programming workshop
  • Programming JavaScript
  • Linux programming
  • Object Oriented Programming
  • Programming the Microsoft Foundation Classes
  • Programming Visual Basic
    (everyone makes mistakes :-)
  • Programming CLIST
  • Application courses

    • HP OpenView Network Node Manager for Network Managers
    • Netscape Integrated Management Solution (Administration server, Directory server, Certificate server, Proxy server)
    • Netscape Publishing Solution (Enterprise server, Compass server)
    • Netscape Messaging Solution (Messaging server, Collabra server, Calendar server)

    Microsoft product courses

    • Windows/NT Core technologies
    • Windows/NT Enterprise
    • Microsoft TCP/IP
    • Microsoft System Management Server


    In addition to teaching courses I am a regular presenter at conferences and workshops. My latest "gigs" include:
    Title Explanation
    The Open Source Phenomenon A presentation together with accompanying white paper (in Dutch) on all aspects of open source and why organisations should consider using open source software.
    The Linux Kongress Kompletely Konfusion Kuiz The Komplete Konfusion Kuiz is a funny (but somewhat weird :-) quiz I hosted at the 2002 Linux Kongress in Cologne. The quiz revolves around quite insane hacker questions involving picture and sound categories.
    Sociological phenomenae at Unix hacker conferences Basically a half-hour stand-up comedy act about the weird stuf you come across at Unix conferences. This act was performed at SANE 2002 and was illustrated with pictures shot at the very same conference :-). There is also a humorous paper with the same title that went into the conference proceedings.
    Linux and Open Source
    Penetrating the organisation
    Was presented as a keynote on LinuxWorld 2001 in Frankfurt. The theme of the presentation was how to pitch Linux and other open source solutions in large organisations. The presentation was repeated on the Linux@Work conferences in Brussels and Amsterdam (June 2002).
    Unix HA clusters
    If you've seen one, you've seen 'm all
    This presentations gives an overview of a number of popular Unix HA cluster solutions such as MC/ServiceGuard, Sun Enterprise Cluster, LifeKeeper, Veritas Cluster Server et cetera. The presentation has a thematic approach, outlining how various vendors/projects solved various aspects of HA clusters.
    Pitfalls in developing interactive web applications A presentation on common mistakes made when developing interactive applications for the World Wide Web. This one was presented at the DBM99 conference.
    Security aspects of system and network management frameworks This presentation was held at the System Management 99 conference. The presentation went into the usually disregarded security aspects of implementing a system and network management framework such as HP OpenView or BMC Patrol.
    High Availability An introductory workshop in all aspects of creating highly available environments. This 1 day workshop touched on all subjects that are of interesting in HA environments such as mirroring, HA-networks and clustering. The workshop was held at the second day of the System Management 99 conference.
    Is Linux ready for the big league? A presentation on whether the Linux operating system is ready to be deployed in enterprise environments. This presentation was held several times, amongst others at the Twente Technical University and at KPN Research.
    To Linux or not to Linux
    that is the question
    An introductory presentation into the art and being of Linux. Held at amongst others the Utrecht University hospital.
    Living Without Windows A presentation derived from the articles. Went into the various aspects of using Unix/Linux for your daily IT instead of the default choice (Windows). This presentation was held at the Catholic University in Tilburg.
    Delivering Quality at NLUUG conferences The famous NLUUG DQN presentation. I usually hold this presentation prior to an NLUUG conference for all program committee members and (Dutch) speakers. The presentation explains how the conference is organized and how to give a good presentation at a technical Unix conference.
    Unix and the year 2000 A presentation that I held at an NLUUG meeting. It covers the Y2K aspects of Unix in general and various specific Unix versions and flavours. It is presumably the only Unix presentation around that contains excerpts (in Latin) from Papal writings...
    Setting up a secure web server A 1 day workshop on setting up a secure (SSL) web server. This workshop was written by me, but delivered by a colleague at the 1997 DutchWorks (HP User Group) conference.
    Which Language or Tool? A humorous comparison between the various programming languages and related tools that we have to our avail in Unix. This presentation was delivered at an NLUUG conference in 1996.
    Trusted Third Parties A presentation on the role of Trusted Third Parties (such as Certificate Authorities) in E-Commerce. This presentation was held at the closing session of a "remote learning' course that I wrote material for.
    Internet Information Shops 1 to 5 A series of workshops I organized which covered the most important aspects of using the Internet for business purposes. The five infoshops covered Internet fundamentals, TCP/IP, E-mail, the World Wide Web and Internet security.


    Another one of my "hobbies" (so as to speak) is writing articles and other texts which explain or comment on technology or techniques. Some of my funniest writing is under a secret pseudonym so I can not mention it here. The following is a non exhaustive list of my more recent writing (also look at the "ArticleWare" section on http://www.josvisser.nl):
    Title Explanation
    Het Open Source fenomeen A Dutch language white paper on the ins and outs of Open Source and why organisations should consider using open source.
    Comal has been set free An article published on the NLUUG E-Zine and other sites about the OpenComal project.
    On ProxyTunnel An article published on the NLUUG E-Zine about a program I wrote that can tunnel SSH connections through HTTP proxies.
    Java column For the Dutch "Software Release Magazine" I used to write a monthly column about the Java programming language and its application.  If you can read Dutch follow this link to get an index of the columns so far.
    Java, from hype to reality An overview article which analyses the Java platform. It covers the period from the platform's first release up until now.
    On NT Password Security An analysis of the Windows NT password mechanism, focused on the encryption and on-the-wire protection. It is much referenced, and can be found here.
    Living Without Windows A series of articles on my switch from Windows to Linux. It can be found here.
    Rock Linux: Not for woozies An article in the NLUUG E-zine on the building and installation of Rock Linux.
    The web comes to life with Java One of the very first articles in the Netherlands about Java applets.
    HP-UX tips & tricks An article with a number of tips&tricks for users of HP-UX. Appeared in the "Open Computing" magazine.
    Windows NT scaleability An article on the scaleability of the Windows NT operating system. The article not only covered traditional SMP scaleability but also investigated how Windows NT scales when being deployed in a Wide Area Network. This article also appeared in the "Open Computing" magazine.
    Open up your directories with LDAP An article on the Lightweight Directory Access Protocol (LDAP) and how it can be used to get at information stored in various directories throughout an organization.
    SoftWindows 95, the best of  both worlds? A product review of the SoftWindows95 Virtual PC.
    System Administration, Unix vs Windows NT An article that compares the administration of a Unix system with that of a Windows NT system.
    WWW server applications, Servlets vs ASP This article compared two technologies for creating WWW server applications. It appeared in the Software Release Magazine.
    Legal aspects of using the Internet A module in a "remote learning" course on using the Internet for business purposes. This article investigates the various legal aspects of Internet use as seen from the Dutch Computer Criminal Code.
    Java Programming I wrote an entire course about Java programming. 
    Advanced Java Programming Guess what? The sequel to the above mentioned course.
    High Availability, dream and reality of 100% uptime An introductory booklet on virtually all aspects of High Availability. It is used as a marketing tool for our HA activities and I used it in a workshop on High Availability at the System Management 99 conference.
    Advanced Korn Shell Programming A set of course notes and examples to support a course in Korn Shell Programming.
    Internet Fundamentals Together with a colleague I wrote a course for Hewlett Packard on the fundamentals of the Internet. This course was splendidly timed to be released at the time the use of the Internet exploded across the western world (1994/1995).
    Romanian Diary Early 2000 I travelled to Romania to teach a Sun Enterprise Cluster course at CFR (Romanian Railways). Now, Romania is a pretty interesting country where a lot of stuff looks and works differently from what one is used to. I wrote an extensive report (with pictures) of everything I went through there. If your Dutch is up to speed, you can amongst other things read how I was almost robbed five times and how a mysterious and beautiful Romanian girl tried to seduce me (or maybe not, ....). If you can't read Dutch, the pictures are still pretty interesting....

    Additionally, as former press officer of the Netherlands Unix User Group NLUUG I used to write comments on misleading Unix/Linux information in Dutch magazines or newspapers. And I obviously write papers and other supporting materials with all my presentations.

    And, to top it off, I am currently writing a book about a very topical Linux subject for a major (and I mean major) publisher. Keep looking at those bookshelves folks!

    Frequently Asked Questions

    In line with Internet standard I include a Frequently Asked Questions (FAQ) list here. Any questions you have that are not answered here or in the rest of my CV can be relayed to josv@osp.nl.
    Q: What is all this MVS and IBM mainframe stuff I keep reading in your CV?
    A: Well, the first four years of my professional career I was an IBM mainframe (MVS) systems programmer. I maintained stuff like DF/HSM, DF/DSS and RACF, wrote user exits in assembler and did other cool stuff with all this big iron.
    Q: In your CV I read mostly stuff on commercial Unix versions. Do you use Linux or any other free Unix-like OS?
    A: Of course I do! I installed and maintain two Internet servers that run FreeBSD (gatekeeper.osp.nl and hedgehog.josvisser.com). On my laptop (jadzia.osp.nl) I run Rock Linux 1.4 with a few Jos Visser specific kernel patches. Furthermore, at OSP we use mainly Linux on our desktops and we develop software under Linux which we then port to other Unix'es.
    Q: What is your stance on Windows NT and other Microsoft products?
    A: Hmm, a tricky question which deserves a long and thoughtful answer. I don't like Microsoft operating systems myself, although some of their end user applications are really good. However, most of my customers use Windows NT somewhere in their IT infrastructure so I have taken it upon myself to know a lot about it so that I can integrate my Unix/Internet work with their PC's. I'd rather not be involved in a Windows-only project though...
    Q: Do you ride a motor cycle?
    A: Yes, a Honda Nighthawk!
    Q: Do you have a family?
    A: No! But I can regularly be seen in the company of a smashing blond-haired blue-eyed babe that is absolutely crazy about me. She is my eight year old daughter Merel.

    Most recent changes on 21-Jan-2003 by yo from Denia.