About me | About this blog


About me

My name is Jerome Tissieres, welcome to my blog.


Jerome Tissieres

Network engineer since 1996, I have a long and successful experience in many different network fields.

I started with Internet services providers

In 1996, I participated in building from scratch the network of one of the first private Internet service providers in Switzerland. Then, I worked for 12 years expanding and operating IP networks for different national Internet service providers. I learned a lot on the job and became a specialist in SP access technologies (dial-up, xDSL/DSLAM, CATV, FTTH). In long-haul transport networks (SONET, SDH, and DWDM). In various WAN technologies like Frame-Relay, ATM, Metro-Ethernet rings, MPLS/VPN services, VPLS, Hierarchical-VPLS, and finally in Segment Routing. On subscribers management (BNG, RADIUS/AAA, QoS, BSS/OSS integration). On routing protocols, especially BGP for edge routing, but also other interior routing protocols. And later, in voice and TV over IP services.

During that time, I was also peering manager: in charge of edge routing, capacity planning, upstreams, IXP, and content providers selection, peering negotiations, and operations. And also all the tasks related to IP prefixes and AS numbers assignment, including a strong collaboration with RIPE NCC.

Then, I switched to enterprise networks

After 12 years in the SP field, I worked for 10 years as an enterprise network engineer. First, for the IMD business school in Lausanne, where I was in charge of the entire campus network (wired and wireless access, the campus core, and edge routing), the network security (segmentation, firewalls, VPNs, IDS/IPS), and the two data-center (data-center and storage networking, load-balancing, domain-names provisioning, SSL/TLS certificates management, I also did a bit of SEO…). Then, I worked as lead network engineer for Interroll, a global manufacturer of products for unit-load handling systems, logistics, and automation. With more than 30 locations worldwide, an international MPLS network, and a 24/7 factory production, it was a very interesting experience.

And finally, almost five years as a senior consulting engineer for Swisscom enterprise, Switzerland’s largest network integrator, and a long-time Cisco gold partner. Where I had the opportunity to lead and implement various enterprise network and security solutions in many different environments such as banks, hospitals, hotels, government agencies, and of course national and international companies. During these 10 years, I have strongly developed my knowledge and experience in enterprise networking and consulting: network planning, design and optimizations, routing and switching technologies, corporate wireless solutions, enterprise security, and mid-size data-center networks.

And now, I work in a data-center

Now, since early 2019, I am working as a senior network and security engineer for the CSCS in Lugano, Switzerland. The CSCS is part of the ETH Zurich, one of the two Swiss Federal Institute of Technology. The ETH Zurich was founded by the Swiss Federal Government in 1854 with the stated mission to educate engineers and scientists, the school focuses exclusively on science, technology, engineering, and mathematics. The CSCS develops and operates cutting-edge HPC (high-performance computing) systems as an essential service facility for Swiss and European researchers. My daily job is to operate and make evolve the in-house high-speed and low-latency data-center network.

You can find my complete professional experience on my LinkedIn page.

I also recently wrote an article for my 25th anniversary as a network engineer.

Learning and certifications

During my career, I also kept an important place for learning and self-study. I love learning, labbing, and discovering new technologies. I also like to share this knowledge with my colleagues and peers. Working as a network engineer for over 25 years, I have constantly learned: on network and telecommunication technologies, of course, but also on design, project management, best practices, troubleshooting methodologies, configurations and fault management, monitoring, scripting, network automation,  and much more! And I am still learning almost every day, which is why I’m passionate about this job.


Industry Certifications

I currently hold the following IT certifications:


Obtained but replaced or discontinued Cisco Certifications

  • Cisco Network Programmability Design and Implementation Specialistreplaced by the Cisco DevNet certification program, in 2020.
  • CCNP Routing & Switching – replaced by CCNP Enterprise, in 2020.
  • CCDP – replaced by Cisco Certified Specialist Enterprise Design, in 2020.
  • CCNA Routing & Switching – replaced by CCNA, in 2020.
  • CCDA – discontinued by Cisco in 2020, with no equivalent.
  • CCIP (Cisco Certified Internetwork Professional) – replaced by CCNP-SP, in 2014.


  • CMNA
  • CMNO #00177


  • HCSA IP Network


  • IPv6 Forum Gold Certified Network Engineer
  • SonicWALL CSSA – Certified SonicWALL Security Administrator
  • Novell Supervisor certified – Novell NetWare 3.11 (Yes! This was during dinosaur times…)


And not CCIE?

No, I am not a CCIE. I passed three times the CCIE Routing and Switching (RS) written exam (versions 4.0 and 5.0) and I failed four times the CCIE RS lab exam in Brussels. Once at the exam version 4.0, in 2013. And three times at version 5.0, between 2016 and 2017. On my last attempt, I was really close to passing (the result was: pass-pass-fail) but after this failure, I realized that I wasn’t learning anything new and that I was practicing more to pass the exam than to learn. So, I decided to stop chasing my CCIE numbers to have more time to learn new technologies.

During this great journey, I took two Narbik Kocharians / Micronics bootcamps and completed multiple times the practice lab workbooks of INE, iPexpert, and Narbik. I also did many practice labs from Cisco expert-level training (formerly Cisco-360). This was a fantastic experience for around five years and I learned a lot!


Cisco Champion since 2019

I am also honored to have been chosen to be part of the Cisco Champion program in 2019, 2020, and 2021.

Cisco Champion 2019 Cisco Champion 2020 Cisco Champion 2021

Personal Side

If you want to know more about me and my other activities, please visit my personal website.



About this blog

“It would be nice to write this in a blog, to help the next person facing the same problem!”

This is what I said, every time I meet a new challenge or problem and cannot find the corresponding documentation. Or when I found undocumented behavior on a network device or protocol. As a network engineer since 1996, I said this phrase millions of times. So here it is now: I created this blog.

I talk here about Cisco, Meraki, Huawei, Mellanox, Cumulus-Linux, and other network systems. The related software for network planning, design, operations, troubleshooting, and automation. And also about my learning experiences in networking, software scripting, and cloud.


Prizes and awards

IT Blog awards finalist in 2018 – 2019 – 2020

My blog has been selected as a finalist in the IT Blog Awards, hosted by Cisco:

  • In 2018 in the Best Cert Study Journey category – provides useful insights into the need-to-knows throughout a certification study journey.
  • In 2019 and 2020 in the Most Educational category – Shares great tips, tricks, or how-to’s to help you learn something new or further your understanding on a topic.
ITBlogAwards_2019_Badge-Finalist-MostEducational_small 2020 IT Blog Awards finalist

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