Senior Network Engineer (Squid Proxy & Palo Alto Security)

• Design, implement, configure and support enterprise Squid Proxy environments, including forward, reverse and transparent proxy deployments.
• Administer and optimise Palo Alto Next-Generation Firewalls, including Panorama management.
• Develop and maintain granular firewall security policies using Palo Alto App-ID, User-ID and Content-ID technologies.
• Configure and manage URL filtering, Threat Prevention, WildFire, GlobalProtect and SSL decryption.
• Manage proxy ACLs, authentication integrations, SSL inspection and web filtering policies.
• Review and optimise firewall rule bases, transitioning legacy port-based rules towards application-aware security policies.
• Troubleshoot complex network and application connectivity issues across Layers 2-7.
• Perform packet analysis using tools such as Wireshark and tcpdump.
• Support firewall and proxy upgrades, migrations, patching and high-availability configurations.
• Work alongside Cyber Security teams to support vulnerability remediation, incident investigations and security compliance activities.

Technologies:

• Ansible
• Architect
• ELK
• Firewall
• Grafana
• Support
• NAT
• Network
• Python
• Security
• Splunk
• TCP/IP
• VPN
• Web

• 5+ years experience supporting enterprise network infrastructure.
• Strong hands-on administration and support experience with Palo Alto Networks firewalls.
• Demonstrable experience configuring and managing Palo Alto App-ID security policies.
• Extensive experience with Squid Proxy, including ACLs, SSL inspection and authentication.
• Experience with Palo Alto Panorama, User-ID, URL Filtering and Threat Prevention.
• Strong understanding of TCP/IP, routing, VLANs, DNS, DHCP, NAT and VPN technologies.
• Experience troubleshooting SSL/TLS, authentication and application connectivity issues.
• Proficiency with network analysis tools such as Wireshark and tcpdump.
• Experience working within highly secure, regulated or business-critical environments.
• Active SC clearance and sole UK national status.
• Desirable: experience in Defence, Government or Critical National Infrastructure, or supporting secure customer environments.
• Desirable: knowledge of network segmentation and Zero Trust security principles.
• Desirable: experience with infrastructure automation using Python or Ansible.
• Desirable: familiarity with monitoring platforms such as Splunk, SolarWinds, ELK or Grafana.