Architect – Voice, Mobile Roaming & IoT

ABOUT US: iBASIS is the leading communications solutions provider enabling operators and digital players worldwide to perform and transform. iBASIS provides the end-to-end Global Access for Things™ connectivity solution, delivering single-source cellular IoT access worldwide, provisioned through GSMA-standard eSIM/eUICC technology. In combination with the Simfony Connectivity Management Platform (CMP), a fully featured platform for remotely programmable SIMs, the iBASIS IoT solution simplifies IoT connectivity through one unified platform for seamless, remote, programmable, and secure communication. iBASIS is the first independent communications specialist, serving 1,000+ customers across 18 offices worldwide. Alongside IoT, iBASIS offers a full portfolio of innovative mobile data, messaging, and roaming solutions in the fastest-growing segments of global telecommunications — IP and mobile — with 700+ connected destinations. Our goal is to be in the global top-3 of IPX players, driven by the growth in LTE and 5G roaming.

WHY US: The iBASIS Global Access for Things portfolio uses GSMA-standardized eSIMs to provide global access with a single SIM and policy-driven control. Leveraging deep relationships with mobile network operators worldwide, iBASIS is a disruptive force in the IoT and roaming industry. In this rapidly expanding domain, you will have the opportunity to shape the future of global connectivity and help position iBASIS as the market leader in IoT, Voice, and Roaming solutions.

About the Role: We are seeking a highly experienced and visionary Architect to join the Voice, Mobile Roaming, and IoT Architecture group within iBASIS. In this strategic role, you will lead the end-to-end architecture, design, and evolution of our global Voice, Roaming, and IoT platforms.

You will define technical roadmaps, drive cross-domain solution architecture, and ensure the scalability, reliability, and security of all signaling, roaming, and IoT services. This role is central to iBASIS’s mission to remain a global leader in IPX, mobile roaming, and next-generation IoT connectivity.

You'll Bring: Bachelor’s or master’s degree in electrical engineering, Telecommunications, or Computer Science with 15+ years of experience in the telecommunications domain. Deep expertise in Voice (TDM & VoIP), Mobile Roaming, and IoT architectures, including end-to-end service design. Extensive hands-on and architectural experience with 3G, 4G, and 5G signalling: MAP, Diameter, SIP/IMS, HTTP/2, GTP-C/U, SBA interfaces, and interworking models. Strong understanding of roaming technologies, including SS7, Diameter Roaming, LTE/VoLTE Roaming, 5G interface, IPX models, and fraud/security frameworks. Proven experience designing and integrating mobile core systems such as HLR/HSS, STP/DRA, SMSC, MME/AMF, SGW/UPF, PGW/SMF, IMS Core, SBCs, and GTP proxies. Expertise in IoT connectivity architectures, eSIM/eUICC, CMP platforms, SIM provisioning flows, and GSMA M2M/IoT standards. Ability to lead cross-functional engineering teams, influence stakeholders, and drive architectural governance. Strong analytical mindset with the ability to be highest level of knowledge for troubleshooting complex signaling and roaming issues across multi-vendor environments.

Good to Have: Experience working with telecom operators, carriers, or global IPX providers. Active participation or collaboration with GSMA, 3GPP, IETF, or similar standards bodies. Strong documentation and architectural modeling skills (UML, sequence flows, high-level and low-level design). Experience with eSIM/Remote SIM Provisioning, SIM Toolkit, and GSMA SGP.02/22/32 specifications. Familiarity with REST APIs, microservices, and cloud-native architectural patterns.

Likely to Have Strong background in IP networking, routing protocols (BGP, OSPF), MPLS, VPNs, and interconnect architectures. Hands-on experience with scripting or automation (Python preferred) for testing, validation, and network automation. Working knowledge of network and signaling test tools such as Spectra, Wireshark, Comprion, Keysight, Spirent, or similar. Experience designing or operating large-scale distributed systems with high availability and low latency requirements