McKesson is an impact-driven, Fortune 10 company that touches virtually every aspect of healthcare. We are known for delivering insights, products, and services that make quality care more accessible and affordable. Here, we focus on the health, happiness, and well-being of you and those we serve – we care.

What you do at McKesson matters. We foster a culture where you can grow, make an impact, and are empowered to bring new ideas. Together, we thrive as we shape the future of health for patients, our communities, and our people. If you want to be part of tomorrow’s health today, we want to hear from you.

About the Role

McKesson is seeking a Senior Network Security Specialist to design and advance secure, resilient, and scalable network infrastructure across enterprise, hybrid-cloud, and on-premises environments. In this senior individual-contributor role, you will shape network security architecture, establish technical standards, and reduce attack surfaces through Zero Trust, segmentation, and secure access strategies.

You will partner with Security, Enterprise Architecture, Infrastructure, and business stakeholders to translate operational and regulatory needs into practical security designs. You will also evaluate emerging technologies, lead architecture reviews, strengthen network visibility, and help ensure critical connectivity services remain secure, available, and positioned for business growth.

What You’ll Do

- Design secure network architectures for hybrid-cloud and on-premises environments using Zero Trust, network segmentation, micro‑segmentation, and secure‑by‑design principles.
- Lead network security architecture reviews, risk assessments, design validation, and the development of reusable security patterns and standards.




- Architect and optimize firewall and perimeter security capabilities, including Palo Alto Networks, Zscaler, HPE Aruba EdgeConnect, secure internet gateways, and web proxy solutions.
- Design secure workforce and device access solutions using Zero Trust Network Access, VPN technologies, Network Access Control, and identity-aware security controls.
- Strengthen threat detection through network traffic analysis, IDS/IPS technologies, security monitoring, telemetry, and security analytics.
- Evaluate technologies, proofs of concept, and vendor solutions to inform network security roadmaps and investment decisions.
- Partner with Security, Enterprise Architecture, Infrastructure, and operations teams to improve resilience, regulatory alignment, and business continuity.
- Provide technical leadership during complex incidents, conduct root cause analysis, and implement sustainable corrective actions and automation.

Basic Requirements

- 7+ years of professional experience in network engineering, including experience with network architecture, security design, or enterprise infrastructure strategy.
- Demonstrated experience designing and implementing secure enterprise networks across hybrid-cloud and on-premises environments.
- Hands‑on experience with enterprise firewall technologies, including policy design, configuration, administration,



and optimization.
- Experience applying Zero Trust, network segmentation, micro‑segmentation, or secure network design principles.
- Experience with routing, switching, and network protocols such as TCP/IP, BGP, OSPF, MPLS, or SD‑WAN.
- Experience producing architecture diagrams, design standards, technical documentation, or security review findings.
- Bachelor’s degree in Computer Science, Information Technology, Engineering, or a related field, or an equivalent combination of education and relevant experience.

Preferred Skills/Experience

- Experience with Palo Alto Networks, Zscaler, and HPE Aruba EdgeConnect.
- Experience with network traffic analysis, IDS/IPS, security analytics, and incident investigation.
- Experience with secure access technologies such as ZTNA, VPN, NAC, secure internet gateways, or web proxies.
- Knowledge of regulatory, compliance, or security‑control frameworks in a regulated enterprise workplace.
- Experience with cloud networking and cloud security architecture.
- Automation or orchestration experience using Ansible, Python, APIs, or infrastructure‑as‑code practices.
- Experience conducting vendor assessments, proofs of concept, capacity planning, and technology roadmap development.
- Relevant certifications such as PCNSE, CISSP, CCNP Security, CCIE Security, or vendor‑specific cloud or security credentials.
- Ability to explain complex security risks and architecture decisions clearly to technical and nontechnical stakeholders.

Travel, Work Environment, and Physical Requirements

Work location, in‑office expectations, and travel requirements will be defined based on the approved

📌 Sr. Network Security Specialist (Mississauga)
🏢 McKesson
📍 Mississauga