  Modern communication strives towards provably secure systems which can be
widely deployed. Quantum key distribution provides a methodology to verify the
integrity and security of a key exchange based on physical laws. However,
physical systems often fall short of theoretical models, meaning they can be
compromised through uncharacterized side-channels. The complexity of detection
means that the measurement system is a vulnerable target for an adversary.
Here, we present secure key exchange up to 200 km while removing all
side-channels from the measurement system. We use mass-manufacturable,
monolithically integrated transmitters that represent an accessible,
quantum-ready communication platform. This work demonstrates a network topology
that allows secure equipment sharing which is accessible with a cost-effective
transmitter, significantly reducing the barrier for widespread uptake of
quantum-secured communication.
