Thesis

Data Sensitivity-Based LLM Routing

Privacy-Preserving Architecture for Enterprise AI

What it was about

Companies run more and more of their work through large language models. Contracts and provider safeguards lower the risk, but you are still trusting a provider to honor what it promised about your data.

Most model routers choose a model by quality, latency or cost. I looked at whether the sensitivity of the data could decide instead. Public work can go to any approved model. Confidential work is restricted to open-weight models an organization can run on its own servers.

The thesis asks two things. How an architecture can enforce that rule rather than leave it written down as a policy, and what changes when confidential work is limited to open-weight models. To answer them I built a proof of concept for an enterprise AI assistant that keeps public, organization-managed and user-scoped information apart, reviewed it against its requirements, traced a demonstration, and ran a pilot at Siili Solutions.

The findings hold for the paths that were evaluated. Self-hosted inference and confidential documents stayed design and discussion topics rather than measured results.

Details

University
Aalto University, School of Science
Programme
Life Science Technologies
Major
Bioinformatics and Digital Health
Supervisor
Prof. Jari Saramäki
Advisor
MSc (Tech) Karoliina Tiuraniemi
Partners
Siili Solutions Oyj, Teknologiateollisuuden 100-vuotissäätiö
Submitted
21 July 2026
Grade
4/5