TOSSI - Telecom Open Source System Integrator
Open telecom, made whole.
TOSSI is the Neutral Foundation for the Open Telecom Stack, built on Open Standards and Open-Source Innovation. We believe technology is strongest when it is whole, uniting Radio, RAN, Core, AI, and Security into an Open, Interoperable, and Enduring Ecosystem.
A Linux distribution for open telecom
A Linux distribution doesn't invent the kernel or every package. It curates the best technologies, ensures they work together, and delivers a system people can trust. TOSSI brings that same approach to telecom, integrating and validating open technologies so builders can focus on innovation, not integration.
Make telecom open - and make it work as one
Telecom runs the modern world, yet for decades it stayed closed. TOSSI exists to change that - to integrate the open telecom stack into a complete, validated, secure network that any operator, nation, or builder can run on open foundations.
The question is no longer whether open source can build a network - there are capable open-source projects for the core, the radio, the RIC and the dataplane. The unsolved problem is making the pieces work together: conformant to the standards, secured end to end, and reproducible in production.
That integration is what turns a pile of excellent projects into a network you can trust. We do it once, in the open - so the community starts from interoperability instead of integration debt, and the next decade of telecom rests on foundations no single vendor can close again. And because a network built today must stay safe for a decade, post-quantum security is woven through every interface from the start.
What we integrate, and what it proves
Each area below is work that runs today, with documentation you can follow and reproduce. TOSSI selects, versions, integrates and validates these pieces so they interoperate end to end.
The FAPI split
A disaggregated FAPI interface, so an L1 from one project drives an L2 from another. Proven across OCUDU, OAI and NVIDIA Aerial.
Hardware acceleration
Inline GPU processing for PRACH and SRS, GPU PRACH offload, and LDPC on an Intel ACC100 accelerator card.
AI-RAN
Machine learning inside the scheduler: learned uplink MCS, BSR periodicity prediction, and predictive CSI.
Non-Terrestrial Networks
3GPP Release 17 NTN, with GEO and LEO testbeds that model the satellite link in software, no RF hardware required.
eBPF and XDP datapath
The user plane moved into the Linux kernel, with PFCP-driven subscriber metering and in-kernel quota enforcement.
Certification
CNTC turns 3GPP and SCAS requirements into automated tests and a per-function pass or fail certificate.
Recently shipped
Releases, testbeds and integration results as they land. See all videos and write-ups.
Extending CNTC: Turning 3GPP and SCAS Requirements into Reproducible 5G Core Control-Plane Certification
Open, reproducible, and secure by default
What TOSSI is
- A neutral, vendor-independent integrator
- Upstream-first - fixes land in the source projects
- Conformance against 3GPP and O-RAN Alliance specifications
- Post-quantum, crypto-agile security by default
What TOSSI is not
- A vendor or a product company
- A hard fork of upstream projects
- A single project - it is the integration of many
- A replacement for 3GPP or the O-RAN Alliance
Build the integrated open telecom stack with us
Start with the reference architectures, bring your network function or app to conform against the baseline, or join the working groups shaping where the stack goes next.