Consulting Team

Below are the principal or lead consultants in the various consulting areas.

Don Keller (Principal, Security Assessments)

Don Keller is an information technology professional with extensive of experience in the U.S. military, a number of Top 100 enterprises, and private consulting. His career includes more than fifteen years as an information security practitioner.

In his previous assignment as manager of Enterprise Services – Security for Schlumberger, Don managed a team responsible for the engineering, implementation, and level 3 support of Schlumberger's information security infrastructure. Other assignments included Global and Regional Operations Manager for the sale and service of information security solutions, product manager for managed security services, and security manager for an IT outsourcing contract.

Don has been active in the security industry. He is a long-time member of the Information Systems Security Association (ISSA), have served on the board of the South Texas Chapter in a number of capacities, including chapter president. He has been a panelist and speaker on information security topics in the U.S. and abroad.

Don holds a Bachelor of Science degree from Brigham Young University, Provo, Utah and a Master's Degree in Business Administration from Phillips University, Enid, Oklahoma. He holds CISSP (Certified Information Systems Security Professional), CISM (Certified Information Security Manager) certifications, and CISA (Certified Information Systems Auditor) certifications.

Theodore Van Rooy (Quantitative Risk Assessment)

Theodore Van Rooy is a Research Analyst with a focus in complex and dynamic systems modeling and prediction. Theodore has worked for various companies including Google Inc. and in several industries (Marketing, IT, Finance, Energy) constructing intelligent pattern recognition software for use in detecting complex patterns and trends.

Theodore holds an M.S. in Applied Mathematics from the University of Colorado, Boulder, where he focused his research in statistics, machine learning, artificial intelligence, non-linear optimization and highly stochastic time series. He also holds a B.A. in Mathematics and a B.A. in Philosophy from the University of St. Thomas (Houston, TX).

David Mehl (Principal, Security Governance and Process)

David Mehl is an IT Professional with over thirty years of service at Chevron. He has extensive leadership experience designing and improving IT products. David has extensive experience leading initiatives around IT Service Management, ITIL Problem Manager, IT Root Cause Analysis Facilitator, and Information Protection, producing tangible results of over $3 million per year in reduced impacts from major incidents. He also has an established record of successful team leadership and facilitation, and is an experienced oil field and process plant engineer with significant contributions in Manufacturing and Control Systems security and reliability.

David has a BS Chemical Engineering with Highest Honors from San Jose State University.

Christopher Lowde (Principal, Security and AD Strategy)

Chris Lowde has over thirty years in IT, twenty six with Texaco and then Chevron. For the past twenty years he has focused on infrastructure architecture and strategy and was a principal architect for moving Texaco's Refining IT architecture to distributed systems. In the early 1990's he was the principal architect for integrating Texaco's messaging systems. He was the principal architect of Texaco's Active Directory system and as a result of the merger with Chevron became the principal architect of the Chevron Active Directory.

Chris holds a degree in Engineering with Honors from the University of Warwick in the United Kingdom. He was a board member of the Directory Enabled Networks (DEN) initiative and has presented papers at the National Petroleum Refiners Association and Microsoft conferences.

 

Angelique Grado (Principal, security leader)

Angelique Thies Grado, certified CISSP (Certified Information Systems Security Professional), is a recent addition to Dexa Systems. Angelique designs, creates, and implements secure information environments for enterprises. She has received numerous accolades and awards in her twenty years of planning, implementing, and testing the security of information and physical resources and has a wealth of both practical and executive experience in corporate and government IT security.

Prior to joining Dexa, Angelique advised, consulted, and led IT and corporate leaders and professionals. This includes serving as an Acting/Temporary CISO to the City of Houston Chief Information Officer in establishing policies and procedures for secure computing, assisting the City's IT staff in establishing an IT Security Strategy within an ITIL structure, and acting as the VP/Director of Operations at CyberEvidence, Inc.

Angelique has also served as an officer in the U.S. Air Force, worked on special engagements with both the FBI and the National Infrastructure Protection Center, and provided information operations support for a European visit to the President of the United States and the Executive Branch staff as well as numerous high-profile communications engagements, including the first ever US Air Force presence in Poland post-cold war.

She holds an MS in Engineering Systems and was previously an EnCase Certified Forensic Examiner. Angelique was also awarded distinguished graduate achievements for communications and officer training and has received numerous awards during her time with the U.S. Air Force.

Herbert Yuan (CTO)

Herb Yuan is CTO for Dexa Systems. Herb retired from Shell after thirty three years in a variety of technology and upstream management positions. His last assignment was CIO for the upstream head office, which included technology and exploration organizations with priorities on high performance computing, information management and software engineering. Herb also served on leadership teams associated with technology organizations as well as initiating the Shell Gamechanger enterprise innovation process. He is serving and has served on a variety of boards. Previously, Herb was Chairman of the board of POSC (later renamed Energistics), on the board of the OpenSpirit Corporation and the advisory board of the Rice Alliance. He currently serves on the board of NSITech as well as on the board of the Hermann Park Conservancy. Herb is a member of the SPE. Herb enjoys cycling, golf and reading. Herb received his PhD in Chemical Physics from the Massachusetts Institute of Technology and his undergraduate degree in Chemistry and Math from the Australian National University.