Sr Engineer, System Design (Microsoft: Directory & Security Services)

As America's Un-carrier, T-Mobile US, Inc. (NASDAQ: TMUS) is redefining the way consumers and businesses buy wireless services through leading product and service innovation. The company's advanced nationwide 4G and 4G LTE network delivers outstanding wireless experiences for customers who are unwilling to compromise on quality and value. Based in Bellevue, Washington, T-Mobile US provides services through its subsidiaries and operates its flagship brands, T-Mobile and MetroPCS. For more information, please visit http://www.t-mobile.comSr Engineer, System Design (Microsoft: Directory & Security Services)

Senior Systems Engineer position with a focus on advanced Forest and Domain design in a highly dynamic environment. Work as part of a team in support of operational and project related activities. Provide advanced technical and operational support to other departments and teams as required in support of business objectives. Provide direction and mentoring to staff members.

Enterprise Core Competencies

Requires competency in customer focus, change & innovation, strategic thinking, relationship building & influencing, talent management, results focus and inspirational leadership.

  • 2+ Years Technical engineering experience
  • Focus: Able to communicate goals in support of the business' mission.
  • Drive: Self-motivated and able to work well under pressure
  • Teamwork: Ability and desire to work cooperatively with others on a team.
  • Communication: The ability to ensure that information is passed on to others who should be kept informed. Express oneself clearly in conversations and interactions with others. Clear business and technical writing skills.
  • Customer Focus: The ability to demonstrate concern and meet external and/or internal customers' needs.
  • Analytical: The ability to tackle a problem by using a logical, systematic, sequential approach.
  • Technical Expertise: The ability to demonstrate depth of knowledge and skill in a technical area.

Minimum Required


  • 5+ years experience in a large Windows environment with a focus on Active Directory (AD) and other X500 directory environments
  • Advanced Forest and Domain design and operations experience in a large enterprise environment
  • Advanced proficiency with Domain administration/AD.
  • Strong customer support/customer service abilities
  • PKI (Public Key Infrastructure) operational and design experience (Venafi experience helpful)
  • Working knowledge of PowerShell and other Scripting languages
  • Expert proficiency with core network service concepts and utilities including DNS, TCP/IP, etc.
  • Knowledgeable in SAN or NAS based environment
  • Knowledge of SOX, PCI, Security
  • Knowledge of and proficiency with ADFS/SAML.
  • Knowledge of and proficiency with Azure AD
  • Advanced troubleshooting skills
  • Ability to lead design reviews, define standards, recommend and establish policies
  • Ability to debug system services
  • Ability to install and configure systems/software unassisted
  • Ability to work in a 24 x 7, on-call environment required.


Minimum Required

  • Bachelor's degree in computer science or equivalent experience in lieu of degree.

Essential Functions

  • Technical System Expertise: Understands computer operating systems, networking protocols, how systems operate and data flows. Aware of current technology benefits and security strategies. Expected to lead and provide level of risk assessments for complex network designs. Deep understanding of the building blocks, interactions, dependencies, and tools required to complete design work. Independent study of current technology and security strategies is expected.
  • Technical Services: Provide senior level technical support for Active Directory related project activities. Provide advanced troubleshooting for other teams with failed applications and systems to determine root cause when related to authentication or directory services. Configure and tune hardware and software to insure optimum performance and resource utilization. Provide 24 x 7 on call support as part of a scheduled rotation with other team members.
  • Innovation: Be self-motivated and able to meet objectives with little or no direct supervision. Recommend, build and modify systems to meet project and user requirements using knowledge of current technology and security strategies. Expected to analyze security risks associated with current planning and offer better solutions when available to minimize security risks. Ability to see possible automation opportunities in current procedures or policies.
  • Technical Writing: Maintains knowledge of existing technology documents. Writes basic documentation on how technology works. Contributes clear documentation on multiple systems used. Able to document systems designs, business requirements and technical interpretation. Develops and provides technical data for incorporation into internal presentations.
  • Technical Leadership: Display strong inter-personal, verbal and written communication skills. Provide consulting, mentoring and technical support to system and user administrators. Collaborates with technical teams and utilizes system expertise to deliver technical solutions. Influence technology and policy decisions made across the appropriate functional organization.
  • Technical Strategy: Participate in design reviews where you serve as the knowledge authority for authentication processes, including Kerberos, LDAP, and SAML (ADFS) integrations. Evaluate hardware and software requirements and influence purchase decisions.

We Take Equal Opportunity Seriously - By Choice T-Mobile USA, Inc. is an Equal Opportunity Employer. All decisions concerning the employment relationship will be made without regard to age, race, color, religion, creed, sex, sexual orientation, gender identity or expression, national origin, marital status, veteran status, the presence of any physical or mental disability, or any other status or characteristic protected by federal, state, or local law. Discrimination or harassment based upon any of these factors is wholly inconsistent with our Company values and will not be tolerated. Furthermore, such discrimination or harassment may violate federal, state, or local law.

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