The Inria Saclay-Île-de-France Research Centre was established in 2008. It has developed as part of the Saclay site in partnership with Paris-Saclay University and with the Institut Polytechnique de Paris .

The centre has 40 project teams , 27 of which operate jointly with Paris-Saclay University and the Institut Polytechnique de Paris; Its activities occupy over 600 people, scientists and research and innovation support staff, including 44 different nationalities.

The TRiBE team at Inria Saclay is offering a 6-month Research and Development Engineer position to implement a private Bluetooth-based communication protocol called BUBBLE-BLUE. BUBBLE-BLUE (BB) is a multihop private communication approach that enables a small group of devices to exchange messages using Bluetooth only, without relying on cellular or Wi-Fi infrastructure. The protocol combines end-to-end confidentiality within the group with controlled multihop dissemination based on Connected Dominating Set (CDS) mechanisms. In practice, since Bluetooth does not natively support broadcasting, message dissemination relies on sequences of unicast transmissions.

• Implement an operational prototype of the BUBBLE-BLUE protocol stack on the target device, including Bluetooth transport integration and a minimal demonstrator application (e.g., secure group chat and optional geo-sharing).
• Explore and assess the security layer assumptions and implementation choices (key distribution, replay resistance, revocation/repudiation handling, overhead, and performance impact).
• Evaluate the resulting system under realistic constraints (mobility/density/traffic) and produce a report on the reproducible experimental results.

• Study the BUBBLE-BLUE preprint to derive an implementable protocol specification, including packet formats, timers, and state machines.
• Define the interfaces between the Bluetooth transport layer, the protocol core for control and forwarding, and the application layer.
• Establish a reproducible test methodology, along with a logging and telemetry strategy, for experimental evaluation.
• Implement the baseline security and packet-processing functions on the target device, including per-packet session keys, encrypted payloads, multi-recipient key headers, sequence numbers, and replay protection.
• Implement the baseline forwarding plane using controlled flooding based on a Connected Dominating Set (CDS) based distributed approaches. 
• Explore and compare alternative routing and forwarding strategies, such as frugal AI-based approaches
• Conduct security analysis, protocol hardening, and experimental validation by assessing threats

• Background in computer networks / wireless systems.
• Programming skills suitable for the target device (e.g., C/C++, Python, or embedded Linux).
• Familiarity with Bluetooth APIs/constraints is a plus.
• Basic understanding of applied cryptography and secure software engineering practices. Ability to run experiments, analyze results, and write a clear technical report

• Subsidized meals
• Partial reimbursement of public transport costs
• Leave: 7 weeks of annual leave + 10 extra days off due to RTT (statutory reduction in working hours) + possibility of exceptional leave (sick children, moving home, etc.)
• Possibility of teleworking (after 6 months of employment) and flexible organization of working hours
• Professional equipment available (videoconferencing, loan of computer equipment, etc.)
• Social, cultural and sports events and activities
• Access to vocational training
• Social security coverage

Regarding professional experience