Poor Internet performance currently undermines
the efficiency of hyper-responsive mobile apps such as augmented
reality clients and online games, which require low-latency access
to real-time backend services. While edge-assisted execution, i.e.
moving entire services to the edge of an access network, helps
eliminate part of the communication overhead involved, this does
not scale to the number of users that share an edge infrastructure.
This is due to a mismatch between the scarce availability of
resources in access networks and the aggregate demand for
computational power from client applications.
Instead, this paper proposes a hybrid edge-assisted deployment
model in which only part of a service executes on LTE edge
servers. We provide insights about the conditions that must hold
for such a model to be effective by investigating in simulation
different deployment and application scenarios. In particular,
we show that using LTE edge servers with modest capabilities,
performance can improve significantly as long as at most 50%
of client requests are processed at the edge. Moreover, we argue
that edge servers should be installed at the core of a mobile
network, rather than the mobile base station: the difference in
performance is negligible, whereas the latter choice entails high
deployment costs. Finally, we verify that, for the proposed model,
the impact of user mobility on TCP performance is low.