Network Test Engineer IP

Three Ireland; Dublin; Hybrid; EUR 65,000 - 90,000; Full time

Benefits offered by this job

Hybrid work model

Healthcare insurance

Leave buy/sell option

Coursera learning access

Free parking at office

Job summary

Three Ireland is seeking a Network Test Engineer (IP) to ensure MCN testing across Voice, Messaging & Data Services, RAN, IP, and VAS. You will manage the Test Lab IP and tooling, ensuring stability to support testing.

You will work with experienced engineers to evolve the mobile network, collaborating across design, solutions & operations to deliver a top-notch customer experience on voice, data, and messaging services.

Qualifications

• Strong background in IP networking and testing frameworks.
• Degree in Engineering or Telecommunications or equivalent experience.
• Experience with enterprise telecom-grade routers, switches, and firewalls.

Responsibilities

• Support deployment and integration of telecom network elements and labs.
• Manage and maintain network test tools and traffic generators.
• Configure and troubleshoot Layer 2/3 networking protocols (VLANs, OSPF, BGP, MPLS, VRRP, QoS).
• Monitor connectivity, latency, and service availability in test and production-like environments.
• Maintain datacentre and lab network infrastructure, cabling, power, inventories.
• Coordinate setup for testbeds, traffic simulators, and capture systems.
• Collaborate with RAN, Core, Security, and Systems Engineering teams.
• Develop automation scripts for backup, monitoring, and test env management.
• Produce network diagrams and test environment reports.

Skills

IP networking

Networking protocols

Linux

Virtualization

Wireshark

iPerf

tcpdump

Communication

Education

Engineering or Telecommunications degree

Tools

Cisco routers

Juniper switches

Fortinet firewalls

Traffic generators

Lab validation platforms

Job description

In our world things change by the millisecond

We build the technology that creates amazing moments and better connects our customers. Ready to play your part? Join us and Be Phenomenal. Working towards the same shared goal of better connectivity, our tech teams enjoy a high degree of freedom. We love hearing ideas and seeing them come to life. With great resources, you’ll get to be part of a team at the foundations of the transformation of our business. Who knows what the next innovation will be? That’s what makes a career at Three so exciting.

Since we set foot in Ireland, we’ve done things differently

Investing in infrastructure, we built a network that now connects 2.2 million customers nationwide, carrying more data than all alternative telecommunications providers combined. We take the script and rip it up, we’re a big-hearted energetic bunch, striving for a better connected life. We encourage our employees to face their weaknesses, to really open themselves up to new tasks and projects in a super-charged and rich learning environment. We want you to become the best version of yourself.

Join us as a Test Engineer (IP)

This position resides in the Three Ireland Networks Test Team; a team which is accountable for ensuring the delivery of all Mobile Core Network (MCN) testing (Voice, Messaging & Data Services, RAN, IP, Service Control and VAS). The primary focus of this role is managing the Test Lab IP and Tooling environment, ensuring stability and availability to support testing across the MCN.

As a Network Test Engineer, you will work alongside a team of experienced engineers tasked with the continued evolution of the Three Ireland mobile network. Collaboration with multi-disciplinary experts across network design, solutions & operations with the goal of delivering first class customer experience on voice, data & messaging services.

The Network Test Engineer position reports to the Networks Test Manager and offers the successful candidate a fantastic opportunity to learn and develop rapidly within a fast paced, dynamic environment, with exposure to a full end-to-end mobile network.

The suitable candidate will have a strong background in IP Networks combined with a solid understanding of testing frameworks and principles.

As a Test Engineeryou will be hands-on across a wide range of Network equipment and technology, contributing to a wide array of solution introductions and existing mobile network validations:

• Support deployment and integration of telecom network elements, servers, and virtualized environments within lab and datacentre infrastructures.
• Manage and maintain network test tools and traffic generation platforms used for validation, performance, and interoperability testing activities.
• Perform configuration, troubleshooting, and optimization of Layer 2 and Layer 3 networking protocols including VLANs, OSPF, BGP, MPLS, VRRP, and QoS.
• Monitor and troubleshoot network connectivity, latency, packet loss, routing issues, and service availability across test and production-like environments.
• Maintain the physical datacentre and lab network environment, including rack installation, structured cabling, patching, power management, and hardware inventory tracking.
• Coordinate physical setup and connectivity for testbeds, traffic simulators, packet capture systems, and telecom validation platforms.
• Collaborate with RAN, Core, Security, and Systems Engineering teams to support end-to-end testing and network integration activities.
• Develop automation scripts and tools for configuration backup, monitoring, and test environment management.
• Produce technical documentation, network diagrams, operational procedures, and test environment reports to support engineering and operational activities.

The skills we're looking for

• The successful candidate should be competent in all aspects of networking, across both physical and virtualised platforms. They must be motivated and driven, with a proven ability to work in both a team environment and autonomously.
• Educated to degree level in an Engineering / Telecommunications discipline, or equivalent experience
• Strong knowledge of IP networking concepts and protocols including TCP/IP, VLANs, OSPF, BGP, MPLS, NAT, VPNs, and QoS. (Minimum CCNA or equivalent)
• Hands-on experience configuring and troubleshooting enterprise or telecom-grade routers, switches, and firewalls from vendors such as Cisco, Juniper, or Fortinet.
• Experience managing network test tools, traffic generators, packet capture solutions, and lab validation platforms.
• Familiarity with datacentre infrastructure, including structured cabling, rack layouts, power distribution, hardware installation, and environmental considerations.
• Ability to troubleshoot complex network performance and connectivity issues using tools such as Wireshark, iPerf, tcpdump, and network monitoring platforms.
• Experience with Linux systems, virtualization technologies, and containerized environments used in telecom or cloud-native deployments.
• Strong analytical, organizational, and communication skills with the ability to manage both logical network operations and physical lab/datacentre environments.

Nice to Have:

• Knowledge of Mobile Core and RAN Network architectures
• Knowledge of network automation and scripting using Python, Bash, or Ansible for configuration and operational efficiency.
• Project and Design lifecycle understanding
• Applicable security qualification (CompTIA Security + or equivalent)

Benefits of Working at Three

• Flexible working with our new Hybrid model, our employees will enjoy more flexibility working from home and our office locations (3 days per week office based). Please see job description for the office location of this role.
• Competitive salary, annual performance bonus & pension contribution
• Annual Leave buy or sell (buy or sell up to 5 days AL each year)
• Healthcare Insurance through our flexible benefits programme
• Access to learning & development tools such as Coursera
• Free on-site parking

There’s a lot more to us than meets the eye.

You may think you know us, but we’re full of surprises. Intrigued? Join us and Be Phenomenal.

At Three, we are committed to equity, diversity and inclusion. As Ireland’s largest mobile telecommunications provider, we provide a better connected life for our diverse customer base, and want our teams to reflect this. We welcome and celebrate all identities and strive to create a culture of belonging where employees can thrive as their authentic selves. If you do not ‘tick every box’ in this job description, you likely have other valuable skills that would make you a great fit for one of our teams. If you feel this role is for you, then

If you require reasonable adjustments for your interview, please let us know when scheduling your interview, or alternatively, please email [e-mail]