Senior Technical Specialist

Singtel Group; Sydney; On-site; AUD 130,000 - 180,000; Full time

Benefits offered by this job

Product discounts

On-site facilities

Parental leave

Wellbeing support

Free counselling

Shuttle to station

Job summary

Optus is seeking a Voice and Data Core Senior Technical Specialist to ensure performance, availability and reliability of critical network services in a 24/7 Tier 2 Network Operations team. This onsite role in Macquarie Park, Sydney, supports Packet Core, IMS, and 5G Core platforms, leading incidents and guiding upgrades.

The successful candidate will mentor teammates, drive continuous improvement and collaborate with engineering and vendors on strategic initiatives to enhance customer

Qualifications

• Deep technical expertise in Mobile Packet and Policy Control (4G/5G).
• Experience in service operations within telecommunications and hands-on network support.

Responsibilities

• Diagnose and resolve faults across Packet Core, IMS, Subscriber Data Management and 5G Core.
• Lead technical escalations during major incidents and coordinate cross-functional teams.
• Perform root cause investigations and drive permanent corrective actions.
• Support and maintain EPC, 5G Standalone Core, IMS and Subscriber Data Management platforms.
• Troubleshoot mobility, data services, subscriber authentication, policy control, VoLTE/VoWiFi issues.
• Analyse signalling and service flows (SIP, Diameter, HTTP/2, REST, SS7, SIGTRAN).
• Collaborate with Engineering and Vendors on upgrades and capacity planning.
• Monitor service performance and drive reliability improvements.
• Represent Operations in CAB and ensure deployment readiness.

Skills

Mobile Core (4G/5G)

CCS7

Diameter

HTTP/2

SIGTRAN

5G Core

Network Operations

Job description

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We don’t sit back and wait for the future to happen, we are out there crafting our own path through new technology, innovation, and investment. We are truly a challenger brand, with challenger spirit.

About the Role

The Voice and Data Core Senior Technical Specialist is responsible for ensuring the performance, availability, and reliability of critical network services within the Tier 2 Network Operations team. The role provides 24/7 operational support across Voice and Data Core platforms, managing incidents, problems, and changes while working closely with vendors and engineering teams to support network enhancements and service improvements.

This position also provides technical leadership, contributes to the delivery of new network capabilities, and mentors team members to drive operational excellence.

Location: Macquarie Park, Sydney (100% onsite)
Work Pattern: 24/7rotating shift roster, including day, afternoon, and night shifts

What You’ll Do

• Diagnose and resolve complex faults impacting Packet Core, IMS, Subscriber Data Management and 5G Core services escalated from Tier 1.
• Lead technical escalations during major incidents, coordinating cross-functional teams to restore services and minimise customer impact.
• Perform detailed root cause investigations and drive permanent corrective actions through structured problem management practices.
• Support and maintain operational performance across EPC, 5G Standalone Core, IMS and Subscriber Data Management platforms.
• Troubleshoot customer-affecting issues relating to mobility, data services, subscriber authentication, policy control, VoLTE and VoWiFi services.
• Analyse signalling and service flows across SIP, Diameter, HTTP/2, REST APIs, SS7 and SIGTRAN protocols.
• Collaborate with Engineering and Vendors to support software upgrades, capacity expansions, technology refreshes and strategic network initiatives.
• Monitor service performance and key operational metrics, identifying opportunities to improve network reliability, customer experience and operational efficiency.
• Represent Operations within Change Advisory Board (CAB) processes and ensure deployment activities meet operational readiness and quality standards.
• Drive continuous improvement initiatives across event management, alarming, automation and operational tooling.
• Support the introduction of new technologies and ensure operational preparedness for future network capabilities.
• Mentor and coach team members, promoting technical excellence, knowledge sharing and operational best practice.

What You’ll Bring

• Deep technical expertise in Mobile Packet and Policy Control (4G and 5G), with deep knowledge of CCS7, diameter, HTTP/2, and SIGTRAN signalling standards.
• Demonstrable experience in service operations within telecommunications, including hands-on network support and troubleshooting preferably on Ericsson Nodes including EPG, MME, WMG, PCC, PCG, CCDM, CCSM, SBG, MTAS, CSCF, HSS, HLR, DRA etc.
• Demonstrated ability to effectively manage technology vendors and maintain strong governance practices.
• Confident in communicating technical concepts, presenting recommendations, and responding effectively to management feedback.
• Proactive problem-solver who takes ownership of issues, investigates root causes, and drives practical, timely solutions.
• Recognised Subject Matter Expert with strong partner engagement skills and a collaborative, relationship-building approach.

The good stuff

• Competitive remuneration, plus $80 monthly credit, 25% off Optus products and exclusive shopping discounts with our retail partners — making everyday life a little more affordable.
• An office campus that has it all - cafes, chill-out zones, GP, post office, gym, and on-site childcare centre. It’s built for real life.
• Great leave policies, including additional 'Connected’ days to focus on culture, family, health, community, or whatever matters most to you.
• Inclusive, carer-neutral paid Parental Leave of up to 16 weeks, because family comes first.
• Build meaningful connections through colleague-led networks and diversity initiatives including Culture Connect, Elevate Women, Disability Network, and Express Yourself (LGBTQIA+).
• Your wellbeing matters, so we offer free counselling and support services, available 24/7 in-person, by phone, SMS, or video.
• A free Optus bus from Macquarie University Metro Station (every 6-8 minutes); morning and afternoon. Or, heaps of onsite parking. Plus, end-of-trip facilities with lockers, showers, irons, and hair dryers.

At Optus, we are strengthened by others and that means valuing diversity and saying ‘yes’ to embracing individual differences. We are committed to ensuring that our application process provides an equal employment opportunity to all job seekers, including individuals from diverse gender, cultural and linguistic backgrounds, individuals with a disability, individuals identifying as being part of the LGBTQIA+ community, individuals who may have served in the armed forces or who identify as Aboriginal and/or Torres Strait Islander. We also want to do our best to make our recruitment process inclusive. If you require any adjustments or accessibility support to participate fairly and equitably in the recruitment process, please [e-mail] or call 1800 309 170.