I explain complex systems, teach the people who operate them, and help organisations reason through consequential technology decisions.
São Paulo · Portuguese and English · work delivered globally
What I do now
Build ronutzThis site: tools that compute rather than guess, articles read from the vendors' own pages, and a record of the industry, all built in the open.
TeachOfficial instructor-led training on the four platforms, virtual and on site, in any time zone.Official courses on F5, Fortinet, Extreme Networks and Netskope. How the courses are taught →
AdviseExecutive-level technical advisory for the decisions that carry business or mission consequences.What the advisory covers →
SpeakTalks and facilitated sessions on networking, security and the craft of making complex things make sense.
Where it started
Before the formal career, there was the curiosity. Through the early 1990s I was importing and assembling computers, running and using bulletin board systems, and working across DOS, Unix, Linux, Netware, early Ethernet, X.25, and dial-up internet. By 1995 that hands-on work had become a first formal role building an electronic-data-interchange system. The thread from then to now is the same: take something genuinely complex, make it work, and make it make sense to someone else. Those have never been separate phases - the teaching started in 1997 and has run alongside every role since.
Why ronutz exists
The tools I wanted while teaching did not exist in a form I could trust: calculators that compute instead of guessing, explanations that cite the vendor's own page, and a record of the industry I lived through that someone else can check. So I built them, in the open, from documentation read live, with nothing a reader types leaving the browser in the catalogue's tools; the two red room lookups that do query a registry say so before they ask, and ask only on the reader's word. The site began as the classroom's companion and grew into a workbench, a knowledge base and a record of the industry; it is free because the knowledge in it was never mine alone.
How I work
Five principles hold across the site and the teaching alike:
Can't write up an endorsement for one company, since I worked w/ him in 3 different companies.
The simple endorsement is the fact that I recommended him for two out of the three places I worked w/ him.
There are few people in the networking industry that not only understand networking technologies, but actually "feel them", Rodolfo is one of these few blessed people.
Luiz EduardoCTO, Security at HPE Aruba NetworkingLinkedIn recommendation · July 22, 2004
My career began on the vendor and implementation side in 1996 and widened from there into systems audits and design, technical and sales enablement - three decades in enterprise networking, two of them hands-on before I focused fully on training. That depth and range is the reason the training lands: I have built, broken, and fixed these systems in production.
1996 – 2000
Cabletron Systems · São PauloNetwork engineer and certified instructor. Non-Ethernet and Ethernet networks, campus networks, IP routing. Cabletron was then Cisco's largest reseller, through the OEM line that put Cisco IOS and Cisco routing inside its own hubs, and I was one of the experts for that line: I went out to customers with feature explanations and configuration examples drawn from the internal documentation CDs Cabletron periodically sent its offices. We called them the "Jeopardize" discs, after the stern warning on each one that distributing the CD or its confidential contents would seriously jeopardize one's job.
2000 – 2002
Riverstone Networks · Santa Clara, CaliforniaProduct support engineer and knowledge-base coordinator in California. Gigabit Ethernet, metropolitan area networks, IP routing, BGP. Third-level escalation, customer scenario recreation, and regression testing.
2003 – 2004
Cisco Systems · BrasíliaNetwork consulting engineer in Brasília, acting as the single point of contact for two of Brazil's federal customers: SERPRO, the government's data-processing agency, and ECT-Correios, the national postal service. Escalation and customer-satisfaction management.
2004 – 2005
IronPort Systems · São PauloChannel development and pre-sales technical consulting for IronPort's C-Series e-mail security appliances: late 2004 with IronPort's own São Paulo operation, then through 2005 with a Cisco and IronPort reseller, from RFPs and installation to customer support. IronPort was acquired by Cisco in 2007.
2005 – 2007
Enterasys Networks · São PauloNetwork engineer and instructor. Enterprise networks, IP routing, user access control and NAC, IDS and IPS.
2009 – 2010
Juniper Networks · São PauloChannel support engineer and instructor for enterprise switches and firewalls. Technical sales enablement and Junos-SRX operations training.
2011 – 2014
Implementation · via CYLK, TDec and direct engagementsDeploying and integrating security and network platforms for end customers, mostly under contracts held by resellers and occasionally direct. Juniper SSG, SRX, EX and Secure Access - the line that became MAG and then Pulse Secure - alongside Cisco ASA, Palo Alto Networks next-generation firewalls, and Extreme Networks Summit and BlackDiamond switches.
2015 – 2019
F5 Networks · Westcon / TD SYNNEX, Network1 / ScanSourceChannel-facing sales and pre-sales engineering for F5, providing technical enablement, proof-of-concept execution, and partner training across distribution. Secondary work in the same years covered FireEye, McAfee, VMware, Ixia and Keysight, and Pulse Secure.
2020 – 2022
Pre-sales and consulting · via CYLKSolutions consulting and pre-sales through CYLK, the São Paulo security integrator, while full-time instruction with its sister company InLearn began: F5 application delivery and security, Palo Alto Networks firewalls, Fortinet, Tenable vulnerability management, CyberArk privileged access and Corvil network analytics, as proofs of concept, designs and customer training. All six hold a mark here, and each has its chapter in the career record.
2020 – present
Full-time instruction · Red Education from 2021 (full-time September 2023)Authorized training instructor delivering official certified courses across F5, Fortinet, Extreme Networks, and Netskope to organizations worldwide. Teaching has been part of the job since 1997, at every role since: internetworking at Cabletron, routing at Riverstone, switching and network access control at Enterasys, JUNOS at Juniper, and vendor enablement across the distribution years. What changed in 2020 is that it became the whole job - F5 courses as a fixed contractor to an authorized training centre in Brazil, widening in 2021 to Extreme Networks delivery on demand for authorized partners in Brazil and Poland, and settling at Red Education, contracted from 2021 and full-time from September 2023.Currently teaching:
Preparing to teach:
The History
Three eras, one through-line: take something genuinely complex, make it work, and make it make sense to someone else. The last part started in 1997 and never stopped; what changed was how much of the week it took.
Every claim on this page has a place where it can be checked: the career chapters, the credentials with their issuing bodies and dates, the endorsements quoted verbatim, the course catalogue, the writing, the earlier sites, and how this site itself is built.
