Senior Network Engineer (Routing & Switching Specialist) - freelance - hybrid, London, UK
Contract Comgent United Kingdom
Posted On 03/09/2026
Job Information
Standard Business working Hours Yes
Work Experience 8-10
City London
State/Province City of London
N/A
Special Considerations
We are committed to building an inclusive workplace and encourage applications from women and other under-represented groups in tech. All qualified candidates are welcome.
Start date: Apr/ May 2026
Location: London, UK (Hybrid - minimum 2 days per week in office)
Job Description
Working closely with the Senior Network Architect, this hands on engineering role is focused on the practical remediation and documentation of a complex, legacy Cisco environment. The successful candidate will be a routing expert capable of diagnosing and unpicking unconventional protocol configurations, building standards compliant designs, and supporting the convergence of two network environments.
Key responsibilities
- Audit and document the existing network estate ( 1,000 devices across both banking entities)
- Identify and remediate non standard routing configurations, including atypical EIGRP deployments
- Define and implement standardised change categories, change risk classifications, and change management templates
- Support the transition from hybrid ACI to target state architecture
- Develop network documentation and operational runbooks
- Provide detailed input into the network baseline assessment
- Act as a subject matter expert during change approval board (CAB) reviews
- Work with managed service providers to ensure designs and standards are followed during implementation.
Requirements Must have
- Expert level Cisco Routing & Switching: IOS, IOS XE, NX OS
- Hands on experience with Cisco Nexus platforms (2K, 5K, 7K, 9K)
- Deep routing protocol knowledge: EIGRP, OSPF, BGP - including troubleshooting of complex or misconfigured environments
- Familiarity with Cisco ACI and spine leaf fabric architectures
- Proficiency with network documentation tools and diagramming
- Experience working in dual stack (legacy + modern) environments
- Understanding of network security segmentation and firewall integration
Advantageous
- CCIE or CCNP (Routing & Switching or Data Centre)
- Automation/scripting experience (Python, Ansible, or similar)
- Experience in financial services or similarly regulated environments
- Detail oriented with a methodical approach to problem diagnosis
- Able to produce clear, well structured technical documentation
- Comfortable working in a fast paced environment with competing priorities
- Constructive and collaborative when working with legacy team members and external managed service providers