Network L3 Engineer in Cheswick

Wavenet is a leading UK-based, fully integrated communications and technology provider with more than 25 years’ experience delivering trusted services to organisations across the public and private sectors. We provide a comprehensive portfolio of solutions including connectivity, cloud services, unified communications, cybersecurity, managed networks, and resilient infrastructure. Our mission is to ensure organisations remain secure, connected, and operational at all times, supported by a blend of innovative technology and highly skilled engineering expertise.

The 3rd Line Network Engineer is a senior technical position responsible for providing advanced support across complex enterprise and ISP-level network environments. The role involves resolving escalated incidents, performing detailed diagnostics, and ensuring the stability and performance of customer networks.

You will support a wide range of technologies across routing, switching, wireless, firewalls, and SD-WAN platforms. Customers include public sector bodies, education institutions, healthcare organisations, and commercial environments with mission-critical systems where reliability, accuracy, and professionalism are essential.

You will own connectivity issues across the entire network stack, from core ISP backbone and WAN circuits right through to customer edge routers, firewalls, LAN switching, wireless networks, and any related on-site infrastructure.

• Supporting the Customer

• Managing and resolving 3rd line network incidents and service requests end to end.
• Supporting complex LAN, WAN, Wi-Fi, security, SD-WAN, and ISP-side environments across multi-vendor platforms, including MPLS networks, carrier routing, leased line circuits, and all associated customer and provider-edge infrastructure.
• Responding to and actioning escalated alerts from network monitoring teams.
• Providing clear, timely communication to customers and internal teams throughout incident progression.
• Working with external suppliers and vendors where appropriate to resolve technical issues.
• Keeping all technical documentation, network diagrams, configuration records, and knowledge articles up to date.

• Ensuring that all incidents and service requests are managed within SLA.
• Maintaining consistent and transparent communication with customers throughout each case.
• Taking full ownership of issues and demonstrating a proactive approach to resolution.

• Delivering a professional and high-quality customer experience.
• Identifying when collaboration or input from other teams is required.
• Supporting service delivery teams with technical updates and case information.

• Producing high-quality, detailed documentation for all technical work carried out.
• Ensuring ticket systems and records are accurate and reflect the current status.
• Closing tickets promptly and appropriately once confirmed resolved.

• Strong understanding of ITIL practices including Change Management, Major Incident Management, Problem Management, and continual service improvement.
• Ability to work effectively with the Major Incident team during high-impact outages, providing clear technical input, next steps, and updates as required.
• Experienced in producing high quality Root Cause Analysis (RCA) reports following major incidents, including evidence gathering, impact assessment, and recommendations for prevention.
• Able to identify recurring patterns or trends across multiple incidents and contribute to Problem Management activities, ensuring issues are documented, tracked, and resolved correctly.
• Ensures all technical work is carried out in a controlled, well-documented manner that aligns with customer processes and established ITIL frameworks.

• Providing experienced guidance and mentoring to 1st and 2nd line engineers.
• Assisting with complex technical investigations and major incidents.
• Contributing to internal training material and knowledge sharing.

• Experience working in large-scale, high-importance network environments including public sector, healthcare, education, and critical commercial operations.
• Excellent verbal and written communication skills.
• Strong analytical capability and problem-solving skills.
• Ability to work under pressure and handle multiple complex cases concurrently.
• High attention to detail and strong documentation discipline.
• Experience using ITSM/ticketing platforms (ServiceNow an advantage).
• A willingness to learn, adapt, and develop professionally.
• A collaborative approach and desire to support the wider technical team.

• Significant experience working at 3rd line level in enterprise or ISP network environments.
• Experience supporting networks with high operational importance and complex technical requirements.
• Hands-on experience with firewalls including Fortinet/FortiGate, Palo Alto, Cisco ASA/FTD, and Meraki MX.
• Strong experience with Cisco routing and switching (ISR, ASR, Catalyst, Nexus).
• Experience with Meraki (MX/MS/MR).
• Knowledge of Cato SD-WAN or similar platforms.
• Exposure to Extreme Networks switching/wireless (beneficial but not essential).
• Strong understanding of: BGP, OSPF, VLANs, spanning tree, trunking, LACP, Firewall policies, NAT, routing behaviour, VPNs, WAN troubleshooting including leased lines, broadband and SD-WAN tunnels.

• Professional-level certifications or equivalent experience, such as: Fortinet NSE 4/5/6, Meraki Technical Specialist (Or equivalent proven experience at the same technical level).

• Experience and Certifications Desired

• Experience with MPLS, fibre circuits, carrier routing, and ISP operations.
• Additional certifications across: Fortinet (NSE 7+), Meraki, Extreme Networks.
• Experience with monitoring tools such as Auvik, LogicMonitor, PRTG, SolarWinds, or similar.
• Good understanding of network security principles and best practice.