  People desire to be connected, no matter where they are. Recently, providing
Internet access to on-board passengers has received a lot of attention from
both industry and academia. However, in order to guarantee an acceptable
Quality of Service (QoS) for the passenger services with low incurred cost, the
path to route the services, as well as the datacenter (DC) to deploy the
services should be carefully determined. This problem is challenging, due to
different types of Air-to-Ground (A2G) connections, i.e., satellites and
Direct-Air-to-Ground (DA2G) links. These A2G connection types differ in terms
of cost, bandwidth, and latency. Furthermore, due to the flights' movements, it
is important to consider adapting the service location accordingly. In this
work, we formulate two Mixed Integer Linear Programs (MILPs) for the problem of
Joint Service Placement and Routing (JSPR): i) Static (S-JSPR), and ii)
Mobility-Aware~(MA-JSPR) in Space-Air-Ground Integrated Networks (SAGIN), with
the objective of minimizing the total cost. We compare S-JSPR and MA-JSPR using
comprehensive evaluations in a realistic European-based SAGIN. The obtained
results show that the MA-JSPR model, by considering the future flight positions
and using a service migration control, reduces the long-term total cost
notably. Also, we show S-JSPR benefits from a low time-complexity and it
achieves lower end-to-end delays comparing to MA-JSPR model.
