Senior Network Engineer

Mimecast Limited; City of Westminster; Hybrid; GBP 80,000 - 100,000; Full time

Job summary

A leading cybersecurity solutions provider in the United Kingdom seeks a Senior Network Engineer to oversee global network infrastructure and operations. You will work with diverse networking platforms like Cisco and Juniper, focusing on performance optimization and security policies while fostering collaboration among IT teams. This full-time role offers a hybrid working model, where you will maintain system reliability and support projects that impact customer experience. Your expertise in networking technologies will be crucial in driving operational excellence.

Benefits

Formal learning opportunities

Comprehensive benefits package

Flexible working model

Qualifications

• Extensive hands-on experience with Juniper platforms including Mist EX switches.
• Strong proficiency with Cisco Meraki solutions for network management.
• Proven experience deploying and managing Aruba wireless infrastructure.

Responsibilities

• Design and maintain global network infrastructure supporting hybrid connectivity.
• Monitor and resolve complex network issues impacting performance.
• Collaborate with security teams to implement network security policies.

Skills

Network engineering expertise

Cisco proficiency

Juniper experience

Wireless technologies

Network automation

Education

Bachelor’s degree in Computer Science

CCNP certification

CCIE, JNCP certifications

Tools

Cisco Meraki

Aruba networking solutions

Opengear devices

Python

Ansible

Job description

As a Senior Network Engineer you will be responsible for the day‑to‑day operation, troubleshooting and continuous improvement of Mimecast’s global corporate network infrastructure. You’ll work with diverse networking platforms including Cisco, Juniper and Aruba to maintain optimal performance and availability. Collaborating closely with IT Security and Workspace teams you’ll resolve complex network issues, implement strategic upgrades and leverage automation to enhance operational efficiency across Mimecast worldwide operations.

Responsibilities

• Design, build, and maintain network infrastructure across Mimecast’s global office locations, including edge routing, enterprise switching, and wireless systems, to support hybrid workforce connectivity.
• Monitor, troubleshoot, and resolve complex network issues affecting LAN, WAN, SD‑WAN, SASE, and wireless services, ensuring optimal performance and minimal downtime for both on‑site and remote users.
• Configure and maintain out‑of‑band management infrastructure to ensure administrative access and recovery capabilities across all network devices globally.
• Collaborate with security teams to implement and maintain network security policies, access controls, and segmentation strategies that protect corporate assets and user data.
• Partner with workspace and IT teams to ensure network infrastructure supports collaboration platforms, productivity tools, and hybrid work technologies seamlessly.
• Develop and maintain comprehensive network documentation, including topology diagrams, configuration standards, runbooks, and change management procedures.
• Lead network upgrade projects and technology refresh initiatives, evaluating new solutions and implementing strategic improvements to enhance performance and scalability.
• Leverage automation tools and scripting to streamline network operations, reduce manual tasks, and improve configuration consistency across multi‑vendor environments.
• Participate in on‑call operations to provide 24/7 network support for critical incidents affecting Mimecast’s global workforce.

Join our Network team to accelerate your career journey working with cutting‑edge technologies and contributing to projects that have real customer impact. You will be immersed in a dynamic environment that recognizes and celebrates your achievements.

Benefits

Mimecast offers formal and on‑the‑job learning opportunities, maintaining a comprehensive benefits package that helps our employees and their family members sustain a healthy lifestyle and build knowledge through cross‑functional teams.

Hybrid Work Model

We provide flexibility to live balanced healthy lives through our hybrid working model. Employees are expected to come to the office at least two days per week due to the benefits of working together in person.

• Fosters a culture of collaboration, communication, performance and learning.
• Drives innovation and creativity within and between teams.
• Introduces employees to priorities outside of their immediate realm.
• Ensures important interpersonal relationships and connections with one another and our community.

Salary Range

The base salary range for this position is + benefits. This range represents the minimum and maximum new hire compensation for this role. The position may also be eligible for incentive plans and additional benefits in accordance with company policy and local regulations.

Equal Opportunity

We’re proud to be an Equal Opportunity and affirmative action employer and we encourage you to join us, whatever your background. We particularly welcome applicants from traditionally underrepresented groups. We consider everyone equally: your race, age, religion, sexual orientation, gender identity, ability, marital status, nationality or any other protected characteristic won’t affect your application. Due to certain obligations to our customers, an offer of employment will be subject to your successful completion of applicable background checks conducted in accordance with local law. It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment.

Required Experience

• A wealth of experience with enterprise network engineering, demonstrating expertise in designing, implementing and supporting large‑scale network infrastructure.
• Extensive hands‑on experience with Juniper platforms, including Mist EX switches and SRX firewalls, including configuration, troubleshooting and optimization.
• Strong proficiency with Cisco Meraki solutions for network management, including cloud‑managed switching, wireless and security appliances.
• Proven experience deploying and managing Aruba wireless infrastructure in enterprise environments with multiple sites and diverse user populations.
• Working knowledge of Opengear or similar out‑of‑band management platforms for remote device access and network recovery.
• Experience with SASE (Secure Access Service Edge) and ZTNA (Zero Trust Network Access) solutions supporting secure hybrid cloud and remote workforce connectivity.
• Comprehensive enterprise wireless planning expertise, including RF site surveys, heat mapping, interference analysis, capacity optimization and adapting to evolving wireless spectrum standards (Wi‑Fi 6 / 6E / 7).
• Strong understanding of network protocols including BGP, OSPF, spanning tree, VLANs, VPN technologies and QoS implementations.
• Experience with network automation and scripting using tools such as Python, Ansible or similar technologies to streamline operations and ensure consistency.
• Bachelor’s degree in Computer Science, Information Technology or related field, or equivalent practical experience. Preferred industry certifications such as CCNP, CCIE, JNCP etc.
• Exceptional communication, interpersonal and collaboration skills with a focus on delivering outstanding user experiences.
• Based in the London, UK office working in a hybrid environment with flexibility for occasional on‑call support and travel requirements.

Employment Type

Full‑time. Experience required: years (unspecified). Vacancy: 1.

Join a passionate and innovative team dedicated to designing, implementing and supporting robust network infrastructure across Mimecast’s global corporate operations. We’re committed to leveraging cutting‑edge networking technologies, automation tools and best practices to deliver reliable, secure and high‑performance connectivity that enables seamless communications, enhances productivity and provides exceptional user experiences for our worldwide family of Mimecasters.