Solutions Engineer (SS7 Signalling and IP Routing)

Skylo Technologies; Finland; On-site; EUR 120,000 - 150,000; Full time

Job summary

Skylo Technologies in Espoo, Finland, seeks a highly technical Signaling and Routing Specialist to turn MNO IR.21/RAEX profiles into production-ready Diameter connectivity and live traffic. You will own the interconnect design, DRA/DEA configuration, IP/DNS readiness, IREG execution, and operational handoff.

You will collaborate with a global team across time zones and help scale Skylo\'s first commercial NTN vRAN platform, joining a core engineering hub with onsite work three days a week.

Qualifications

• 10+ years of hands-on experience in mobile-core signaling, roaming interconnect, telecom solutions engineering, or network operations.
• Deep technical Diameter experience, including DRA/DEA configuration, realm routing, peer management, and S6a/S6d/SGd protocols.
• Strong IP interconnect fundamentals, including DNS/ENUM, routing, security controls, and firewall/ACL coordination over IPX/GRX networks.
• Advanced protocol analysis skills with the ability to read Wireshark traces to independently diagnose signaling failures.
• Proven experience translating complex IR.21/RAEX data into operational configurations and executing structured IREG validation.
• A disciplined approach to change management, documentation, configuration integrity, and live production risk.

Responsibilities

• Routing Configuration: Design and configure Signaling, DRA/DEA routing, peers, connections, realms, Diameter identities, and GT mappings.
• Profile Translation: Translate IR.21/RAEX inputs into accurate, version-controlled operational configurations.
• IP & DNS Coordination: Plan interconnect IP addressing and coordinate DNS/ENUM, APN, realm resolution, firewall, and IPX changes.
• IREG Execution: Own end-to-end IREG-side testing for network registration and S6a/S6d authentication.
• Trace Analysis: Analyze signaling traces (Wireshark) and resolve failures across Skylo, the IPX provider, and the partner MNO.
• Component-Level Isolation: Collaborate with Skylo IPX partners and MNO IPX teams to isolate routing issues.
• Standardization: Create change-control, peer-review, rollback, and LL Design documents for interconnections.
• Cross-Functional Partnering: Work with Network Engineering, NOC, Security, Product, and external MNO teams through go-live and stabilization.

Skills

Diameter

Mobile-core signaling

IP interconnect

Wireshark analysis

IR.21/RAEX data

Tools

Wireshark

Job description

The world still has coverage blind spots. You could help eliminate them at Skylo.

Skylo has pioneered a standards-based approach to satellite connectivity. We connect smartphones and IoT devices directly to satellites. No special hardware, no entirely new networks. Just billions of existing devices, suddenly reachable anywhere on Earth. We're not building toward this future. We're already in it.

Our direct-to-device service is live on millions of activated devices across five continents, covering more than 72 million square kilometers, in partnership with leading satellite operators, mobile network operators, Tier-1 chipset makers, and OEMs worldwide. And we're just getting started.

At the heart of it all is Skylo's commercial NTN vRAN: a 3GPP standards-based, cloud-native platform that seamlessly bridges terrestrial and satellite networks. It's the infrastructure that makes true anywhere, anytime connectivity possible.

When you join Skylo, you'll work at the intersection of three markets reshaping how the world stays connected: mass-market consumer devices, automotive, and industrial IoT. Enabling people outdoors and critical workflows in the world's most remote places.

This is a rare chance to work on technology that matters, at a company that's already proving it works.

This role is based in Espoo, Finland, one of Skylo's core engineering hubs and fastest-growing sites. You'll work onsite three days a week as part of a team that's scaling quickly. You will collaborate with a high-velocity, global team spanning multiple time zones.

About the Role

Skylo is seeking a highly technical, hands-on Signaling and Routing Specialist to turn each Mobile Network Operator's (MNO) IR.21/RAEX profile into production-ready Diameter connectivity and validated live traffic. You will own the operational technical path from interconnect design through DRA/DEA configuration, IP/DNS/ENUM readiness, IREG execution, troubleshooting, and operational handoff.

Responsibilities

• Routing Configuration: Design and configure Signaling, DRA/DEA routing, peers, connections, realms, Diameter identities, and relevant GT and point-code mappings.
• Profile Translation: Translate IR.21/RAEX inputs into accurate, version-controlled operational configurations.
• IP & DNS Coordination: Plan interconnect IP addressing and coordinate DNS/ENUM, APN, realm resolution, firewall/ACL, and IPX peering changes.
• IREG Execution: Own end-to-end IREG-side testing for network registration, attach sequences, S6a/S6d authentication, SGd SMS, and NIDD where applicable.
• Trace Analysis: Analyze signaling traces (Wireshark) and resolve failures spanning Skylo, the IPX provider, and the partner MNO.
• Component-Level Isolation: Navigate and collaborate with Skylo IPX partners and MNO IPX teams to isolate routing and configuration issues at the component level.
• Standardization: Establish clean change-control, peer-review, rollback, and documentation practices, creating LLD (Low-Level Design) documents for every interconnection.
• Cross-Functional Partnering: Partner with internal Network Engineering, NOC, Security, Product, and external MNO technical teams through go-live and stabilization.

Required Qualifications

• 10+ years of hands-on experience in mobile-core signaling, roaming interconnect, telecom solutions engineering, or network operations.
• Deep technical Diameter experience, including DRA/DEA configuration, realm routing, peer management, and S6a/S6d/SGd protocols.
• Strong IP interconnect fundamentals, including DNS/ENUM, routing, security controls, and firewall/ACL coordination over IPX/GRX networks.
• Advanced protocol analysis skills with the ability to read Wireshark traces to independently diagnose signaling failures.
• Proven experience translating complex IR.21/RAEX data into operational configurations and executing structured IREG validation.
• A disciplined approach to change management, documentation, configuration integrity, and live production risk.

Preferred Qualifications

• NB-IoT NTN, NIDD, MME registration troubleshooting, SS7/MAP, STP, or IoT roaming experience.
• Hands-on experience with Signalling & IP configuration in Core network.
• Automation experience using Python, APIs, infrastructure as code, or network testing frameworks.

What We Offer

• This is a once-in-a-lifetime opportunity to help build and run the world's first commercial, live direct-to-device satellite network.
• You'll work alongside a world-class team spanning software, hardware, chipsets, telecom, satellite, and network virtualization, some of the most sought-after expertise in the industry.
• And you'll do it inside a culture that's open, transparent, and inclusive, shaped by the best of Silicon Valley, Nordic, and South Asian ways of working.
• With employees working across three continents, Skylo is proud to be an equal opportunity employer dedicated to building an inclusive and diverse workforce.
• Our worldwide and inclusive culture encourages a flexible approach to work.