Senior Network Security Engineer in Cambridge

Senior Network Security Engineer – Zscaler

Contract: Initial contract

Day Rate: Flexible / dependent on experience

Location: Hybrid – 1–2 days per week in either Cambridge or Macclesfield (not both)

Start: ASAP

The Role

We are looking for an experienced Senior Network Security Engineer to join a major enterprise technology and security programme.

This is a hands-on position focused on designing, implementing and maintaining secure enterprise network infrastructure, with particular emphasis on Zscaler ZPA/ZIA, firewall technologies and network security architecture.

You will work within a large-scale enterprise environment, collaborating with infrastructure, security and wider technology teams to strengthen network security and support ongoing transformation initiatives.

Key Responsibilities

• Design and implement secure enterprise network architectures.
• Configure, manage and troubleshoot enterprise firewall technologies, including Palo Alto, Cisco or equivalent.
• Work extensively with Zscaler Private Access (ZPA) and Zscaler Internet Access (ZIA).
• Support the implementation and ongoing improvement of Zero Trust/network security solutions.
• Conduct security and vulnerability assessments and support remediation activities.
• Work with intrusion detection/prevention technologies and wider network security tooling.
• Monitor and analyse security events using SIEM platforms and support incident response.
• Collaborate with security and infrastructure teams around IAM and Network Access Control (NAC).
• Work within established enterprise ITSM, CMDB, governance and change processes.
• Support security compliance and audit requirements.

We are particularly interested in candidates with:

• Strong commercial experience within Network Security Engineering / Network Security Consulting.
• Hands-on Zscaler ZPA and ZIA experience – this is a key requirement.
• Strong experience configuring, managing and troubleshooting enterprise firewalls, ideally Palo Alto and/or Cisco.
• Good understanding of secure network architecture, encryption and network security principles.
• Experience with IDS/IPS technologies.
• Exposure to SIEM tooling and security incident response.
• Experience working within complex, large-scale enterprise environments.
• Strong troubleshooting and analytical skills.
• Ability to communicate effectively with technical teams and wider stakeholders.

The underlying requirement specifically lists ZPA/ZIA and hands-on firewall configuration and troubleshooting as essential experience.

Desirable Certifications

Any relevant security/network certification would be advantageous, including:

CCNP/CCIE Security, Zscaler certifications, Cisco CyberOps, PCNSA/PCNSE, CCSA/CCSE, CISSP or CompTIA Security+.

Working Arrangement

This is an Outside IR35 contract operating on a hybrid basis. Candidates will need to attend either the Cambridge or Macclesfield location approximately 1–2 days per week – you are not required to travel between both locations.

Day rate is flexible and will depend on experience.