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# Senior Network Security Consultant (Cisco Firewalls)

- **Company:** Cadence Resourcing Ltd
- **Location:** London, UK
- **Experience:** Expert
- **Contract:** Temporary contract
- **Skills:** Border Gateway Protocol, Catalyst (Software), Network Security, Network Layer, Routing, Firewalls (Computer Science), Cisco Firewalls, Routing & Switching, Cisco Switches, Cisco
- **Published:** August 17, 2026
- **Apply:** https://www.careerboard.com/pt/en/find-jobs-in-United-Kingdom/-8C9EB90F841D023490/

## About the Role

We are seeking a high-calibre Senior Network Security Consultant for a 6-month contract to lead the greenfield design, deployment, and Legacy migration of a mission-critical Cisco infrastructure. This role requires an expert-level blend of next-generation security engineering and advanced Layer 3 routing (BGP), alongside the ability to manage physical cutovers on-site in London., Expert Cisco Security: Proven track record deploying Cisco Secure Firewall (FTD) and FMC 7.x in high-availability enterprise environments.

Advanced Routing: Deep expertise in BGP engineering, including manipulation of route maps, prefixes, AS-Path prepending, and communities.

Cisco Catalyst Expertise: Hands-on experience with Catalyst 9300 series, IOS-XE, StackWise technology, and Legacy-to-modern switching migrations.

Certifications: CCIE Security or CCIE Enterprise Infrastructure (Routing & Switching) is highly desirable.

## Description

Cisco Secure Firewall: Architect and deploy a new Cisco FMC HA pair, onboard 4 pairs of Secure Firewalls (FTD) in HA mode, and migrate/optimise Legacy policies to current L7 best practices.

Advanced Routing: Design and implement complex BGP routing architectures across the Firewall estate to ensure deterministic traffic paths and seamless failover.

Switching Upgrade: Plan, stage, and execute the physical and logical migration of 2 Legacy Catalyst 3850 switch stacks to new Catalyst 9300 platforms with minimal downtime.


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