Network Engineer

Company cultures & job summary

Our client is looking for an experienced Network Engineer to support the delivery and optimisation of Cisco ISE and enterprise wireless platforms in a secure Defence environment.

You'll need strong hands-on experience with Cisco Catalyst 9800 WLCs and Cisco ISE, including 802.1X, RADIUS policy enforcement, and wireless integration.

You will be working on two specialist Cisco services and experience in the below technologies is essential

Working Patterns and location – Hybrid – 2-3 days on site per week

·        Lead design, build, and migration of legacy wireless infrastructure to Cisco Catalyst 9800 WLC architecture.

·        Define and deliver end-to-end wireless migration strategies including planning, cutover, and post-implementation optimisation.

·        Architect and implement high-availability 9800 WLC deployments with SSO and redundancy to minimise service disruption.

·        Own design, upgrade, and lifecycle management of Cisco ISE environments including HA topology and patching strategies.

·        Design and enhance secure network access solutions using 802.1X and MAB across wired and wireless environments.

·        Troubleshoot complex authentication and connectivity issues using packet capture and deep protocol analysis tools.

·        Produce clear technical documentation, runbooks, and support artefacts to governance standards.

·        Manage vendor escalations and Cisco TAC cases, supporting change and release management activities.

·        Strong hands-on experience deploying and supporting Cisco ISE in enterprise environments.

·        Deep expertise in 802.1X (wired and wireless), MAB, RADIUS authentication flows, and EAP methods (PEAP, EAP-TLS).

·        Proven experience with Cisco Catalyst 9800 (IOS-XE) WLCs including CAPWAP, AP join, and mobility/roaming.

·        Strong knowledge of WLAN configuration including policy profiles, SSID segmentation, RF optimisation, and seamless roaming.

·        Solid core networking fundamentals including TCP/IP, VLANs, trunking, BGP, OSPF, and EIGRP.

·        Experience troubleshooting end-to-end authentication flows across Client, AP, WLC, and ISE.

·        Ability to perform packet-level troubleshooting using Wireshark and TCPdump.

·        Experience working within structured change and release management processes.

The client would also like to see some of the below, but this is not essential:

·        Experience with Cisco DNA Center for network management and automation.

·        Experience with ForcePoint Firewalls in an enterprise or secure environment.

·        Basic automation or API exposure including ISE and IOS-XE REST APIs.

·        Relevant certifications such as CCNP Enterprise, CCNP Security, Cisco ISE Specialist, or CWNA/CWNP.

Our client is committed to providing a diverse and inclusive workplace and welcomes applications from all backgrounds.

Part-time opportunities/flexible working is available to suit individual needs.

Please note that the client has determined that the off-payroll working rules will apply to this assignment and therefore this contract will be run through an Umbrella Company. Income tax and primary national insurance contributions will be deducted at source from any payments made to the intermediary.

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You will be required to hold a minimum of SC Clearance. If you do not hold an active SC Clearance, please familiarise yourself with the vetting process before applying.

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