Software Engineer - Telecommunications

Imagine being at the forefront of technology that keeps the world connected, from everyday mobile users to first responders on critical missions.

Join a global leader in communication technology with a storied legacy of innovation, delivering cutting edge mobile devices, mission critical communication systems, and intelligent connectivity solutions; celebrated for award winning design, durability, and performance, trusted by major carriers, enterprises, and emergency services worldwide, and recognised for creating iconic products that blend engineering excellence with practical, real world impact.

Seize the opportunity to innovate and grow with a team that is shaping the future of communication and making connections that matter every day.

Responsibilities

• SIP Signaling & Session Management: Develop C# components for high-concurrency SIP sessions, managing complex headers and MIME bodies to support features like "First-to-Answer" and Group Regroups.
• Real-Time Media Plane: Implement RTP/RTCP media handling for Mission Critical Voice (MCPTT) and Video (MCVideo), ensuring seamless floor control (transmission rights) in half-duplex environments.
• Data & Configuration: Build handlers for MCData services (SDS, File Distribution) using HTTP and SIP MESSAGE requests, and manage XCAP retrieval logic for XML configuration documents.
• Secure Communications: Integrate OIDC authentication flows and MIKEY-SAKKE encryption to ensure media transport remains secure and resilient.

Required Qualifications

• C# / .NET Framework / .NET Core Mastery: 3+ years of professional experience with a deep focus on asynchronous network programming.
• .NET Frameworks Experience: WCF, SignalR, EF, ASP.NET, WebAPI
• Protocol Expertise: A solid understanding of the SIP Protocol Stack (INVITE, PUBLISH, SUBSCRIBE, etc.) and experience with RTP/RTCP stacks.
• Data Handling: Proficiency in parsing complex XML schemas (XSD) and handling multipart/mixed MIME bodies.
• Software Engineering Principles: Strong grasp of OOP, SOLID principles, and modern CI/CD workflows (Git, Pull Requests, Agile).

Preferred Skills

• 3GPP Standards: Familiarity with TS 24.379 (MCPTT) or related MCX standards.
• Security: Experience with SRTP, TLS, or Key Management lifecycles (KMS).
• Domain Knowledge: Previous experience with UK Police Control Room environments or the Emergency Services Network (ESN).

Contract Details

• 6 Months
• Start Date: ASAP

Salary

• Rate: £40 Per Hour