Senior Network Security Engineer F5

h3Mission Overview: /h3 pKeystone Solutions is seeking a Senior Network Security Engineer with expertise in F5 to ensure the security of applications and IT environments amidst the challenges of digital transformation. This consultancy mission will take place on-site at our client’s location, where you will represent Keystone Solutions. /p h3Responsibilities: /h3 pAs a consultant, you will be responsible for managing, securing, and continuously evolving the F5/AWAF infrastructure, while also monitoring and evaluating the security status of IT systems. You will be expected to intervene effectively in crisis situations. /p h3Key Deliverables: /h3 ul liInstalled, configured, and managed F5 / Advanced Web Application Firewall infrastructure. /li liDeveloped, documented, and monitored the application of security policies. /li liConducted technical risk analyses on various IT systems. /li liImplemented solutions to address identified vulnerabilities. /li liProvided recommendations on technical solutions for securing partner connections (intranet/internet). /li liProduced technical documentation and incident/crisis reports. /li /ul h3Main Tasks: /h3 ul liManage the F5 Security infrastructure: F5, Advanced Web Application Firewall. /li liPerform installations, configurations, and management of F5
- AWAF. /li liDevelop, document, and monitor the application of security policies. /li liContinuously monitor and evaluate the security status of IT systems against malicious actions. /li liEffectively intervene in crisis situations (organized attacks, network intrusions, virus detection, etc.). /li liAdvise on technical solutions for securing connections with external partners via intranet and internet. /li liConduct technical risk analyses for management purposes on various IT systems. /li liImplement solutions to address potential vulnerabilities. /li /ul h3Key

Skills:
/h3 ul liInstallation, configuration, and management of F5 AWAF infrastructure (APM, ASM, LTM, Identity Provider, SSL VPN). /li liContinuous monitoring and evaluation of system security status; crisis management (attacks, intrusions, viruses). /li liTechnical risk analysis and remediation of vulnerabilities. /li liKnowledge of network and application firewalls (Palo Alto, Forcepoint, Panorama) and VPN/proxy solutions. /li liRigorous documentation and clear communication to teams and management. /li /ul h3Communication and Collaboration: /h3 ul liStrong written and verbal communication skills; able to document work clearly (reports, documentation). /li liAbility to work in a team; methodical, precise, and client-oriented approach. /li liBilingual preferred (French, Dutch) or sufficient basic knowledge of a second national language; technical English is essential. /li /ul h3Level and

Experience:
/h3 ul liExpert and autonomous execution under general direction (SFIA level 4 – Enable), senior technical profile. /li liMinimum 5+ years of experience in IT security, autonomy, initiative, and ability to intervene effectively in crisis situations; explicitly not a junior role. /li /ul h3Education: /h3 ul liGraduated or licensed in computer science or electronics, or equivalent through proven experience. /li /ul h3Practical Information: /h3 ul liStatus: Recruitment / external mission. /li liResponsibility Level: SFIA level 4 – Enable (senior technical). /li liReports to: Network Security Team Leader. /li liWork Regime: Full-time; remote work possible. /li liTeam: Network Security team, in collaboration with systems, operations, and project teams. /li /ul h3Duration: /h3 p01/11/2026
- 31/12/2026 2 months (full time) /p h3Skills required: /h3 ul libFirewalls et filtrage : routeurs, firewalls stateful packet inspection, firewalls applicatifs (Palo /b
- Level: Confirmed
- Most recent: Any time /li libOutils de monitoring et corrélation de logs (Splunk, Nessus, Elastic SIEM) /b
- Level: Confirmed
- Most recent: Any time /li libProtocoles et sécurité réseau : TCP/IP, HTTP/HTTPS, SSL, SNMP /b
- Level: Confirmed
- Most recent: Any time /li libSécurisation des réseaux sans fil (WiFi, WEP, WPA, WPA2) et principes de chiffrement (clé publique/p /b
- Level: Confirmed
- Most recent: Any time /li libSolutions VPN (remote access et site-to-site) et Web proxy ; solutions terminal-serveur (Citrix) /b
- Level: Confirmed
- Most recent: Any time /li /ul h3Language

requirements:
/h3 pDutchbr/Level Active knowledgebr/Englishbr/Level Active knowledgebr/Frenchbr/Level Active knowledge /p