Telecommunications Technical Authority

Role Overview

• Build and validate a comprehensive inventory of telephony assets across multiple sites, ensuring accuracy of existing data and identifying any gaps or risks.
• Assess lifecycle status, supportability, and regulatory exposure across the estate, highlighting operational and safety considerations.
• Define standardised IP/SIP-based architectures covering operational telephony, safety systems, control room environments, and cloud-based solutions such as Teams.
• Align telecommunications designs with wider network, OT, cyber security, and resilience principles.
• Develop clear dial plans and numbering strategies to support the future estate.
• Create structured, site-by-site migration roadmaps aligned to investment plans and business priorities.
• Plan and oversee transitions including ISDN to SIP migration, PSTN retirement, PBX replacement or consolidation, and DDI migration to cloud platforms.
• Produce detailed migration runbooks and fallback strategies to ensure continuity of service.
• Act as the technical design authority, reviewing and challenging third-party designs and ensuring alignment with best practice.
• Ensure quality of service, resilience, failover, and safety compliance are embedded into all solutions.
• Support the delivery of change while maintaining availability of operational and safety-critical services.
• Produce clear and maintainable documentation including architecture standards, inventories, and resilience models.
• Contribute to knowledge sharing and support internal teams to build long-term capability.

Requirements

• Extensive experience working within enterprise or industrial telecommunications environments.
• Proven experience delivering PSTN/ISDN retirement or transformation programmes.
• Hands-on experience with Avaya and/or Mitel systems, including migration and administration.
• Strong understanding of SIP trunking, session border controllers (SBCs), and carrier migration processes.
• Knowledge of VoIP networking principles including QoS, VLANs, and failover design.
• Experience working within regulated or safety-critical environments.
• Strong communication skills, with the ability to engage both technical and non-technical stakeholders.

It would be great if you also had:

• Experience within energy, utilities, oil & gas, or similar industrial environments.
• Exposure to Microsoft Teams telephony (Direct Routing or Operator Connect).
• Experience supporting control room or emergency telephony systems.
• Understanding of resilience frameworks, NIS2, or safety compliance standards.

Tech Stack

• Cloud
• Cyber Security
• VoIP

Benefits

• Personalised Career Development: We create a development plan customised to your goals and aspirations, with a range of learning and development opportunities within a culture that encourages growth.
• Flexible working: Flexible work arrangements to support your work-life balance. We can’t promise to always be able to meet every request, however, are keen to discuss your individual preferences to make it work where we can.
• A Fantastic Benefits Package: This includes generous annual leave allowance, enhanced family friendly benefits, pension scheme, access to private health, well-being, and insurance schemes.