3rd Line Network Engineer

Salary: £45,000 - 50,000 per year

• Strong experience within 3rd Line Network Support, advanced 2nd Line or a senior Network Engineering role
• Ideally, experience within an ISP, telecoms, carrier or service provider environment
• Strong routing and switching fundamentals, including TCP/IP and BGP
• Ability to troubleshoot complex network faults methodically rather than relying solely on predefined scripts
• Hands-on experience configuring carrier or enterprise-grade network equipment
• Experience making changes to live, customer-facing network infrastructure
• Good understanding of change control, technical documentation and configuration management
• Experience owning customer-impacting incidents from escalation through to resolution
• Strong written and verbal communication skills, including the ability to explain technical problems clearly to non-technical customers
• Experience troubleshooting enterprise wireless networks
• Experience carrying out remote wireless diagnostics while supporting engineers on-site
• Scripting or API knowledge for network diagnostics and automation
• Understanding of Layer 1 fibre networks
• Experience with network monitoring, alerting and ticketing platforms
• Relevant professional certifications across routing & switching, firewalls and/or wireless networking

• Own complex and escalated network faults through to full resolution
• Troubleshoot issues across routing, switching, wireless and customer network infrastructure
• Make and document configuration changes on live customer-facing network equipment under change control
• Work with customers, field engineers, suppliers and internal network teams to diagnose and resolve incidents
• Troubleshoot wireless issues remotely, supporting engineers on-site with surveys, access point placement, cabling and power checks
• Develop deep technical knowledge across our wireless networking platforms
• Escalate core network issues to Network Operations with the diagnosis and customer impact already established
• Monitor network events with the potential to impact multiple customers and correlate these against incoming incidents
• Lead problem management for recurring faults, identifying root causes and driving permanent fixes
• Produce clear Root Cause Analysis (RCA) and Reason for Outage documentation for customer-facing incidents
• Develop technical playbooks and documentation to improve resolution rates across 1st and 2nd Line Support
• Improve network monitoring and alerting by tuning thresholds, reducing unnecessary alerts and identifying gaps in coverage
• Manage technical escalations with third-party suppliers and connectivity providers
• Provide technical input on complex customer network configurations before they go live
• Participate in the on-call rota as the senior technical escalation point behind 2nd Line

• API
• Support
• Network
• TCP/IP

More:

We are a leading London-based connectivity and technology organisation hiring a 3rd Line Network Engineer to provide senior-level technical support across business-critical customer networks. This is a hybrid role based in London, offering a salary of up to £50,000, plus a share scheme, private healthcare, pension, and 25 days annual leave plus bank holidays. You will work closely with 1st and 2nd Line Support, Network Operations, field engineering teams, third-party suppliers and customers, taking ownership when incidents require deeper technical investigation. The role offers hands-on exposure to live customer-facing network environments, the chance to work across routing, switching, wireless and connectivity technologies, and support towards advanced professional networking certifications.

last updated 36 week of 2026