  Previous geographic routing schemes in Delay/Disruption Tolerant Networks
(DTNs) only consider the homogeneous scenario where nodal mobility is
identical. Motivated by this gap, we turn to design a DTN based geographic
routing scheme in heterogeneous scenario. Systematically, our target is
achieved via two steps: 1) We first propose "The-Best-Geographic-Relay (TBGR)"
routing scheme to relay messages via a limited number of copies, under the
homogeneous scenario. We further overcome the local maximum problem of TBGR
given a sparse network density, different from those efforts in dense networks
like clustered Wireless Sensor Networks (WSNs). 2) We next extend TBGR for
heterogeneous scenario, and propose "The-Best-Heterogeneity-Geographic-Relay
(TBHGR)" routing scheme considering individual nodal visiting preference
(referred to non-identical nodal mobility). Extensive results under a realistic
heterogeneous scenario show the advantage of TBHGR over literature works in
terms of reliable message delivery, while with low routing overhead.
