David Liu

  • New York NY
  • ganymededl@gmail.com

Work History

Work History
Oct 2010 - Present

Senior Systems Engineer

Grey Global Group
  • Subject Matter Expert in supporting Grey's multi-domain Active Directory and collaboration systems
  • Project lead in the onboarding/offboarding of advertising affiliate companies from Exchange to Exchange solutions (Office 365/LiveOffice), including onboarding multiple offices in North America & LATAM into a global enterprise infrastructure leveraging ADMT, GPO, Powershell Scripting.
  • Design, deploy, and implement Grey's North American/Latin American messaging upgrade from Exchange 2003 to 2010 (5000 mailboxes), with focus on site resiliency & high availability, and disaster recovery.
  • Manage messaging technology projects from requirements gathering, designs, implementation, to maintenance and close-out for the Americas, including Blackberry server upgrades, migration initiatives (migration of 12000 users from on-premise Exchange (2010) to Office 365), implementing Single-Sign-On (SSO) solutions with ADFS-Shibboleth and dirsync, MDM, On-prem messaging archiving (Enterprise Vault), and Mail hygiene migration (Postini to Proofpoint)
  • Monitor & support Grey’s messaging systems, including qmail-ldap, ADFS 3.0/FIM, AD, and Exchange.
  • Establish and document global policies & standards for these core messaging initiatives.
  • Automatie generation of health reports and maintenance for messaging related services using Powershell scripting.
Mar 2010 - Oct 2010

Infrastructure Operations Manager

Grey Global Group
  • Planned, directed, and managed the daily operations, maintenance, and procedures of Infrastructure environment for three major media companies and its 200 nodes multiplatform server farm.
  • Established department policies and procedures and perform daily incident management for server problems using Service-Now.
  • Steered team project and project initiatives, and providing technical guidance for consolidation of various fileservers into single DFS namespace, managed and executed Active Directory migrations involving multi-platform desktops and Windows/OsX/Linux servers, and providing backup support for messaging services.
  • Maintained and monitored compliance to corporate security and Sarbanes-Oxley policies; Create and maintain technical documentation.
Feb 2007 - Mar 2010

North American It Manager

Grey Global Group
  • Managed day-to-day Help Desk and Desktop Support operations with focus on incident management and delivering customer service and speedy problem resolution within established SLA. (On average over 1000 tickets a month that are received for over 1500 users).
  • Supervised a team of 6 IT Support specialists and Regional IT Managers; Manage team projects including annual hardware refresh, desktop inventory, software deployment, Antivirus & patch management, file server migrations & office relocation.
  • Administered Windows 2003 Servers and Exchange for 500 user in multiple domain forest,
    including DNS, Group Policy creation, on/off boarding of user accounts, managing access controls and domain structure configuration.
  • Designed and integrated customized OsX builds. Centrally manage distribution of all software, packaged updates, software licensing for 350+ mac users using Casper Suite.
  • Researched system issues and trained staff and end users on SOP’s, security practices, and , IT Security/SOX compliance standards.
  • Established IT procurement, vendor relationships and set equipment standards. Recommended, purchased, and evaluated IT assets.
Feb 2005 - Feb 2007

Information Security Engineer

Grey Global Group
    • Install and maintain security infrastructure, including log management, daily monitoring and ensuring system robustness of Symantec AntiVirus, Cisco Wireless, Windows Patch Management, Checkpoint Firewalls, Mcafee Intrushield IDS, Checkpoint & Microsoft VPN.
    • Lead engineer for enterprise AntiVirus incident-handling procedures:
      • Provided regular AntiVirus Executive Summary Reports to management on threat/risk management and malware containment.
      • Published regular security Updates newsletters & advisories for global IT infrastructure.
    • Assessed threats, risks, and vulnerabilities and devised security proposals to ensure adherence to the goals of overall information security strategy as well as creation and implementation of new security procedures. 




University of Toronto


Binghamton University SUNY


Information Technology professional with experience in infrastructure operations, maintenance, and security of Windows 2003/2008/2012 systems, served as a subject matter expert for a global advertising company. Ability to manage, evaluate, and troubleshoot systems as well as lead projects with broad knowledge of Active Directory, Microsoft Exchange 2003/2010, Blackberry servers, and vmware.