The Role: We are seeking a high-level E2E 5G Core & IMS Architect to lead the design and governance of our national Voice and SMS Scam Prevention infrastructure for a large telecommunications operator in Sydney. This is a strategic, high-impact role responsible for blending cloud-native 5G Core, IMS, and messaging capabilities into a resilient, automated, and future-ready architecture. You will be the primary technical authority ensuring our mobile and fixed networks are not only cutting-edge but fully compliant with Australia's evolving regulatory landscape. Core Responsibilities : Architectural Governance: Lead end-to-end solution architecture for Optus Mobile and Fixed core networks. Scam & Fraud Mitigation: Design E2E architectures to detect and block spoofing, smishing, CLI manipulation, and bot-generated traffic. Regulatory Compliance: Ensure all designs meet ACMA, TSSR/SoCI, and the 2025 Telecommunications Security and Risk Management Program (TSRMP) rules. Network Convergence: Drive the evolution of VoLTE, VoNR, and Fixed Voice SIP, ensuring seamless interworking and softswitch migration. Technology Leadership: Evaluate and govern vendor platforms including SMS Firewalls, Voice Firewalls, and fraud-management systems. What You Bring : Expert 5G Knowledge: Comprehensive understanding of the 5G Service Based Architecture (AMF, SMF, UPF, PCF, etc.) and signaling protocols (HTTP/2, SIP, SCTP). IMS & Voice Mastery: Experience with P-CSCF/S-CSCF, TAS/MMTel, and SBC policy enforcement. Security Expertise: Proven background in SMS Firewalls, STIR/SHAKEN frameworks, and anomaly-based filtering. Australian Regulatory Savvy: Demonstrated ability to interpret and apply ACMA Scam Codes and SoCI/TSSR requirements. Cloud-Native Proficiency: Experience with cloud-security and automated, closed-loop mitigation workflows. Why Apply? Are you ready to design the future of network security and make a real impact across the industry? Apply now by uploading your resume in WORD format. I f you have further questions contact Shankar Sapkota via email or via mobile on 0403494584.