Tom Gillis

Senior Vice President and General Manager

Security Business Group

Tom Gillis is the Senior Vice President and General Manager of the Cisco Security Business Group (SBG). A respected security industry leader with strong executive management skills and in-depth knowledge of the challenges surrounding secure enterprise computing, Tom is responsible for the company's global security business to fundamentally simplify the security experience. Prior to Cisco, Tom was the SVP/GM of the Network and Advanced Security Business Group at VMware, where he led the endpoint, networking, load balancing and network security businesses. He was also the CEO/co-founder of Bracket Computing which was acquired by VMware. Before Bracket Computing, Tom was the GM of the Security Technology Group at Cisco where he led the company’s businesses for security management, appliances, applications, and endpoint services. Tom was also part of the founding team at IronPort Systems and served as senior vice president of marketing when the company was acquired by Cisco. Under his guidance, IronPort grew an average of 100 percent year-on-year for seven years. During his tenure, IronPort rose to become the leading provider of antispam, antivirus, and antimalware appliances for organizations ranging from small businesses to the Global 2000. Tom has also worked at iBEAM Broadcasting, Silicon Graphics, and Boston Consulting Group in various technical and leadership roles. He is also a noted advisor to startups and venture capital companies and is a member of several boards of directors. Tom holds an M.B.A. degree from Harvard University, and graduated Magna Cum Laude with an M.S.E.E. degree from Northwestern University and a B.S.E.E. from Tufts University.


December 21, 2023


Defining the Future of Multicloud Networking and Security: Cisco Announces Intent to Acquire Isovalent

3 min read

Building out our security cloud vision, Cisco announces its intent to acquire Isovalent. Together we will create a unique multicloud security and networking capability to help customers accelerate their digital transformation.

April 24, 2023


XDR and the Importance of Cross-Domain Correlated Telemetry

2 min read

You need enough data to correlate lateral attacks, which is why a true XDR solution is such a game changer. Learn more about this development.

February 7, 2023


All in for Security: Cisco Secure at Cisco Live EMEA 2023

3 min read

Our Cisco vision for an integrated Security Cloud continues to evolve as we introduce key innovations at Cisco Live EMEA, like Risk-Based Authentication and Business Risk Observability. We also dive into key security trends outlined in our new Security Readiness Index report.