  Photon losses are the main obstacle to fully photonic implementations of
device-independent quantum key distribution (DIQKD). Motivated by recent work
showing that routed Bell scenarios offer increased robustness to detection
inefficiencies for the certification of long-range quantum correlations, we
investigate DIQKD protocols based on a routed setup. In these protocols, in
some of the test rounds, photons from the source are routed by an actively
controlled switch to a nearby test device instead of the distant one. We show
how to analyze the security of these protocols and compute lower bounds on the
key rates using non-commutative polynomial optimization and the
Brown-Fawzi-Fazwi method. We determine lower bounds on the asymptotic key rates
of several simple two-qubit routed DIQKD protocols based on CHSH or BB84
correlations and compare their performance to standard protocols. We find that
in an ideal case routed DIQKD protocols can significantly improve detection
efficiency requirements, by up to $\sim 30\%$, compared to their non-routed
counterparts. Notably, the routed BB84 protocol achieves a positive key rate
with a detection efficiency as low as $50\%$ for the distant device, the
minimal threshold for any QKD protocol featuring two untrusted measurements.
However, the advantages we find are highly sensitive to noise and losses
affecting the short-range correlations involving the additional test device.
