About JP

JP Vossen
  • Co-author of O'Reilly's bash Cookbook 2nd and bash Idioms.
  • Information Security and Linux engineer, Bash enthusiast, automation/tooling developer, and compulsive documenter.
  • Former Co-maintainer of the Snort.org RPMs.
  • Former “Infrastructure and Network Security (esp. Snort) expert” for SearchSecurity.TechTarget.com's “Ask the Expert” feature.

Bio:

JP has been working with computers since the early 1980s and has been in the IT industry since the early 1990s, specializing in Information Security since the late 1990s. He spent some of that time working as a consultant and many years as a Senior Security Engineer for Counterpane Internet Security (then British Telecom after they acquired Counterpane). He was also Director of Customer Support for SGP Technologies (Blackphone.ch) for a short while, but prefers hands-on technical work.

Mr. Vossen has worked with Linux, DOS, Windows, UNIX, VMS and AS/400 platforms, with duties ranging from first-level technical support to network and security architecture and design. He loves to work with Linux, Bash, Python, Perl, and other Open Source and Free Software. Unlike many of his technically inclined colleagues, he also enjoys writing and documentation, which has led to the publication of various InfoSec articles, scripts and tips, O’Reilly’s bash Cookbook 2nd, and bash Idioms.

He has worked with networks from Netware Lite and Netware 3.x on up to 30+ site TCP/IP WANs. He has written programs in COBOL, Pascal, C, BASIC, CMD Batch files, Bash, Perl, Python, and many application macro languages including VBScript. He has also been a beta tester for Microsoft (Win95 and NT4), Symantec, and others, and is still in Microsoft’s Insider program.

JP is also a CISSP and is or was a member of CSI, ISSA ( Delaware Valley), InfraGard (Philadelphia Chapter), SANS, PLUG, and other industry-related groups.


Job:

See my Resume and code on Github.

What I like to do:

I am a force multiplier: I really enjoy writing tools and documentation that make other people’s jobs easier, faster, and more reliable.

  • Write documentation, ideally in Markdown or AsciiDoc (I am a compulsive documenter).
    • I love “Docs-as-Code” and have been doing that much longer than it’s had that name (I had .txt files in CVS).
  • Write “tools” in Ansible, Bash, Python, and Perl to simplify and automate things to make everyone’s job easier, faster, and to make processes more consistent and reliable.
  • Get code organized and into revision control.
  • Solve problems or find solutions (I am a compulsive troubleshooter).
    • I find a problem or build a tool, document it, automate it, put it in version control, establish a repeatable process around it, and make sure nobody has to think about it again.
  • Build processes around tasks (which ties in to all of the above).
  • Work with Linux (mostly Debian and Linux Mint), and other Free and Open Source software.
  • Work with other smart people I can both learn from and teach.

I am a “maker” and work best with solid, uninterrupted blocks of time during which I can fully focus on a task (see Maker’s Schedule, Manager’s Schedule).

Certifications:

  • CISSP (Certified Information Systems Security Professional) #11049, granted March 4, 2000; current.
  • Microsoft Certified Systems Engineer (MCSE); late 1990’s.
  • CheckPoint Firewall-1 v3.x Certified Systems Engineer (CCSE); mid-late 1990’s.
  • WatchGuard Certified System Professional (WCSP); mid-late 1990’s.
  • Novell 3.x CNA (Certified Novell Administrator); mid 1990’s.

Tools:

  • See the Windows port of Logcheck page for my Windows port of logcheck, the famous UNIX log processing tool. You can also download the PowerPoint presentation I gave to the Philadelphia Area Network Technologies User Group ( PANTUG) on September 12, 2001.
  • I have written a couple of management scripts for CheckPoint Firewall-1 (LogSwap & CPFWBack). See my Firewall-1 tools section for more information.
  • I have also packaged an NTP service that will run on a really hardened NT server (unlike the non-free MS TimeServ service). See my Firewall-1 NTP tools section for more information.

Publications & Whitepapers:

NOTE: sadly, a lot of these links are dead due to paywalls and/or other link-rot. I’ve left them here as a reference just in case anyone really needs to try to track anything down.


My Education:

I went to Oratory Prep High School, in Summit, NJ.

I also have a BSIS (BS Information Science) from The University of Pittsburgh.

University of Pittsburgh Logo


My Hobbies and Interests include:

  • Reading, mostly hard science fiction and vampire books.
  • Target shooting, pistol, rifle and bow.
  • Experimenting with Information Security, Linux, Bash, Perl, Python.
  • SCUBA and skin diving (was PADI certified by O’Donnel Diving and Lahaina Divers in early 2001)! See also the Diver’s Alert Network and my SCUBA Pictures--Hawaii 2001 page.
  • Skydiving! I’ve only done one tandem jump so far, at the United Parachute Club but… :-)
  • Working on my car (up to late 2003 that was a ‘93 Honda Civic del Sol Si, now it’s the ‘04 Acura TL 6 speed).
    • See my ASCII “circuit” diagram for a headlight buzzer for early 90s Civics, including the del Sol: here.
  • Rock climbing at the Philadelphia Rock Gym.
  • Fixing things and working around the house (see the infamous Plastic Deck ).
  • Woodworking and metalworking.
  • Kayaking on various local rivers in an Ocean Kayak Malibu Two. Our old one is pretty nice, the new one is much nicer.

Subsections of JP

JP Vossen, CISSP

Collegeville, PA | jp@jpsdomain.org | https://www.linkedin.com/in/jp-vossen-cissp-14b757/

Senior Security Engineer | Automation, Docs-as-Code & Engineering Productivity

Co-author of bash Cookbook (O’Reilly 1st 2007, 2nd 2017) and bash Idioms (O’Reilly 2022).

Information security professional since 1997, with a background in IT dating to 1991 and predominantly remote work since 2002. A hands-on senior individual contributor and force multiplier who thrives on solving problems, making complex or repetitive tasks simpler, more reliable, and easier to maintain. I find a problem or build a tool, document it, automate it, put it in version control, establish a repeatable process around it, and make sure nobody has to think about it again.

CORE COMPETENCIES & TECHNICAL SKILLS

  • Core Competencies: Problem Solving, Troubleshooting, Technical Writing & Documentation (especially Docs-as-Code), Scripting & Automation for Engineering Tooling, Engineering Enablement & Productivity, Process Improvement, Version Control, Code Review, Copyediting, Information Security, Remote Work & Distributed Team Collaboration.
  • AI & LLM Tools: ChatGPT, Claude, Gemini, Microsoft Copilot, Ollama.
  • Cloud Platforms: AWS (foundational), Linode.
  • Development & Collaboration Tools: Atlassian, Git, Forgejo, Subversion, Redmine.
  • Configuration Management Tools: Ansible, Terraform (foundational).
  • Documentation & Publishing Tools: AsciiDoc, HTML, Hugo, Markdown, MkDocs, Pandoc, Wikis.
  • Infrastructure Tools: BackupPC, Etckeeper, Icinga2, Logcheck, NTP, OpenSSH, Opsview, Postfix, Proxmox, RANCID.
  • Operating Systems: Debian, Linux Mint, Red Hat Enterprise Linux (RHEL), Oracle Linux (OEL), CentOS, Rocky Linux, Ubuntu.
  • Scripting & Languages: Bash, Graphviz, Perl, Python, Regular Expressions (PCRE).

PROFESSIONAL EXPERIENCE

British Telecom, BT Americas, Dallas, TX December 2015–September 2026

Senior Security Engineer — BT Assure Threat Monitoring, Reston, VA (Remote)

Hands-on team lead for an international engineering team supporting security infrastructure across five global data centers, with a focus on automation, tooling, configuration management, and engineering productivity.

  • Consolidated six Ansible patching scripts into a shared library and Bash wrapper, eliminating duplicated and inconsistent code while adding features and improving reliability, consistency, and reporting for a 12-person team across ~20 monthly and ~30 quarterly patching tasks.
  • Developed Python-based API data extractors to retrieve authoritative CMDB data for downstream automation.
  • Streamlined engineering workflows across multiple teams through automation, documentation, version control improvements, troubleshooting, and process standardization.
  • Collaborated on design, implementation, debugging, and QA of Assure Threat Monitoring systems.

Silent Circle, Washington, DC April 2014–October 2015

Senior Systems Engineer, March 2015–October 2015 (Remote)

Supported, automated, and improved IT systems for global customer service, IT, and Engineering.

  • Wrote and updated documentation for multiple groups.
  • Assisted with operations across global data centers using ESXi and Ganeti/KVM (CentOS, Debian, Ubuntu); Ansible configuration.
  • Developed Bash and Perl automation and provided technical support for the Engineering team.

Director, Customer Support, April 2014–March 2015 (Hybrid)

  • Designed/built the customer support operation for global rollout of Blackphone.
  • Wrote most initial support documentation; edited the remainder.

Counterpane Internet Security (acquired by BT) January 2002–April 2014

Acquired by BT Americas (Dallas, TX) in October 2006; formerly headquartered in Cupertino, CA.

Senior Security Engineer, May 2005–April 2014 (Remote)

Delivered custom Red Hat/CentOS Linux security platforms for managed log monitoring, retention, and intrusion detection.

  • Implemented automated and semi-automated signature update systems, increasing reliability and reducing processing time by 50%.
  • Improved processes, automation, and documentation across Platform Delivery.
  • Collaborated on system design, debugging, QA, troubleshooting, training, and mentoring.
  • Maintained Linux development and testing environments.
  • Developed Bash and Perl automation and provided technical support to multiple teams.
  • Facilitated version control with CVS/SVN and documentation in MediaWiki.

Integration Manager, January 2002–May 2005 (Remote)

Managed integration of customer networks into Counterpane’s managed security monitoring service.

  • Ensured customer satisfaction and successful service adoption.
  • Developed and updated the Integration Methodology for new customers.
  • Performed research/testing to integrate unique customer environments into monitoring workflows.

TechTarget SearchSecurity.com, Needham, MA January 2004–December 2005

Technical Writer (Freelance / Remote)

  • Wrote monthly “Network Security Tip” articles for SearchSecurity.com and Network Security Newsletter.
  • Answered user-submitted security questions in the “Ask the Expert” forum.
  • See https://www.jpsdomain.org/jp/ for pointers to published articles.

Information Security Magazine, Norwood, MA January 2001–December 2003

Technical Editor (Freelance / Remote)

  • Tested new security products and wrote technical reviews.
  • Researched/wrote feature pieces on network security technologies and practices.
  • Provided technical fact‑checking for editorial staff.
  • See https://www.jpsdomain.org/jp/ for pointers to published articles.

OTHER PROFESSIONAL EXPERIENCE

  • AlphaNet Solutions, Inc. — Wayne, PA | Network Consultant I / II / III | 1997–2002
  • The Reohr Group, Inc. — Valley Forge, PA | Consultant | 1994–1997
  • Day & Zimmerman Information Solutions — Radnor, PA | Systems Support Analyst | 1993–1994
  • Popular Club Plan — Garfield, NJ | PC Support Specialist | 1991–1993

CERTIFICATIONS

  • Certified Information Systems Security Professional (CISSP) since 2000.
  • See LinkedIn for older certifications.

EDUCATION

  • BS, Information Science — University of Pittsburgh.
  • Minor: English Writing.

Vossen's Law

Law

The likelihood of a repair or modification working is directly dependent on whether you’ve reassembled everything without testing it first and inversely proportional to the difficulty of disassembling everything in the first place.

Corollary #1

If it is REALLY difficult to remove and replace, you will break something else just as you get it back together after fixing the first thing.

This really became clear to me working on servers (especially rack-mounted), cars (especially Hondas) and small electronics. But it seems like it should apply to just about anything that is a pain to get at or disassemble.


Other IT Notes

There is nothing more permanent than a “temporary” solution.

The two hardest problems in IT are:

  1. Naming things (& DNS).
  2. Cache invalidation.
  3. Off-by-one errors.