Microsoft Teams External Calling & Session Border Controller Engineer

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JOB DESCRIPTION
Microsoft Teams External Calling &
Session Border Controller Engineer
Recruitment profile for Teams Phone, Direct Routing, SIP and SBC engineering
Rank    Supervising Associate / Assistant Director, based on experience
Service Line    Enterprise Technology | Enterprise Communication & Collaboration
Location    Philippines
Employment Type    Full-time
The opportunity
We are seeking an experienced Microsoft Teams Voice Engineer with strong expertise in Microsoft Teams External Calling, Teams Phone, Direct Routing and Session Border Controller technologies. The role is responsible for designing, deploying, supporting and optimizing enterprise voice services while maintaining operational stability, regulatory alignment and a consistent user experience across global locations.
The successful candidate will combine hands-on engineering capability with strong troubleshooting, stakeholder management and service ownership. The role requires practical knowledge of VoIP, SIP signalling, SBC platforms, carrier integrations, telephony migrations and Microsoft Teams Voice architecture.
Your key responsibilities
Microsoft Teams Voice and external calling
•    Design, implement and support Microsoft Teams External Calling and Teams Phone solutions.
•    Configure and manage Teams voice routing policies, dial plans, calling policies, emergency calling policies and caller ID policies.
•    Enable and troubleshoot PSTN connectivity through Teams Direct Routing.
•    Support migration from traditional PBX platforms to Microsoft Teams telephony.
•    Configure and support Auto Attendants, Call Queues and user voice enablement.
Session Border Controller engineering
•    Deploy, administer and maintain enterprise SBC infrastructure.
•    Configure SIP trunks, routing rules, normalization and interoperability between Teams, carriers and telephony platforms.
•    Troubleshoot SIP signalling and media issues using traces, logs and end-to-end call-flow analysis.
•    Perform SBC software upgrades, patching, certificate management, resiliency validation and failover testing.
•    Maintain secure and highly available SBC configurations in accordance with change and release controls.
Voice infrastructure and carrier integration
•    Coordinate SIP trunk provisioning, DID management, number porting and PSTN service activation with telecom carriers.
•    Validate voice quality, routing, redundancy and disaster-recovery capabilities.
•    Lead technical troubleshooting with carriers, Microsoft and SBC vendors.
•    Support regional and country telephony deployments, migrations and service transitions.
Operations, automation and service improvement
•    Provide advanced L3/L4 technical support for Teams Voice and SBC services.
•    Investigate call-routing failures, one-way audio, media-quality degradation, policy errors and SBC incidents.
•    Participate in major incident response, root-cause analysis and corrective action planning.
•    Automate recurring administration and validation activities using PowerShell.
•    Create and maintain technical documentation, operational procedures, support playbooks and knowledge articles.
•    Drive proactive monitoring, standardization and continuous service improvement.
Skills and attributes for success
Area    Required capability
Microsoft Teams    Teams Phone, Direct Routing, Teams Admin Center, voice routing, dial plans and calling policies
SBC platforms    Strong experience with AudioCodes, Ribbon, Oracle SBC or Cisco CUBE
Voice technologies    SIP, RTP/SRTP, TLS, VoIP, PSTN, number management and call-flow analysis
Microsoft platform    Microsoft 365 administration, Entra ID and PowerShell
Networking    TCP/IP, DNS, DHCP, firewalls, NAT, QoS, LAN/WAN and network troubleshooting
Diagnostics    Teams Call Analytics, Call Quality Dashboard, Wireshark and SBC trace analysis
Service management    Incident, problem, change, major incident and vendor-management practices
Experience and qualifications
•    Eight or more years of experience in unified communications, collaboration or voice engineering.
•    Eight or more years of hands-on experience with Microsoft Teams Voice, Teams Phone or Direct Routing.
•    Demonstrated experience managing enterprise SBCs and SIP carrier connectivity.
•    Experience supporting production voice services and resolving complex incidents.
•    Experience working with global stakeholders, telecom carriers and technology vendors.
•    Bachelor’s degree in engineering, computer science, information technology or a related discipline, or equivalent practical experience.
Preferred certifications and knowledge
•    Microsoft certification aligned to Teams administration or collaboration communications.
•    AudioCodes, Ribbon, Oracle SBC or Cisco Collaboration certification.
•    ITIL Foundation or practical experience in IT service management.
•    Knowledge of emergency calling requirements such as E911 or E112.
•    Experience with ServiceNow, monitoring platforms and telephony automation.
What we look for
•    Strong analytical and structured problem-solving skills.
•    Clear written and verbal communication with technical and non-technical stakeholders.
•    Ability to work effectively across cultures, time zones and matrixed teams.
•    Ownership mindset, attention to detail and commitment to service reliability.
•    Ability to lead technical discussions, document decisions and coach junior engineers.
Measures of success
•    Stable, secure and highly available Teams Voice and SBC services.
•    Timely incident resolution and high-quality root-cause analysis.
•    Successful carrier, SBC and country integration outcomes.
•    Increased automation, standardization and operational efficiency.
•    Positive stakeholder and end-user experience.
Recruitment note: The final rank and scope should be calibrated to the candidate’s depth of architecture ownership, hands-on SBC administration, global deployment experience and production support accountability.

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