  The future Quantum Internet is expected to be based on a hybrid architecture
with core quantum transport capabilities complemented by conventional
networking.Practical and foundational considerations indicate the need for
conventional control and data planes that (i) utilize extensive existing
telecommunications fiber infrastructure, and (ii) provide parallel conventional
data channels needed for quantum networking protocols. We propose a
quantum-conventional network (QCN) harness to implement a new architecture to
meet these requirements. The QCN control plane carries the control and
management traffic, whereas its data plane handles the conventional and quantum
data communications. We established a local area QCN connecting three quantum
laboratories over dedicated fiber and conventional network connections. We
describe considerations and tradeoffs for layering QCN functionalities,
informed by our recent quantum entanglement distribution experiments conducted
over this network.
