  With the increasing availability of mobile devices that natively support
Device-to-Device (D2D) communication protocols, we are presented with a unique
opportunity to realize large scale ad hoc wireless networks. Recently, a novel
D2D protocol named WiFi Direct has been proposed and standardized by the WiFi
Alliance with the objective of facilitating the interconnection of nearby
devices. However, WiFi Direct has been designed following a client-server
hierarchical architecture, where a single device manages all the communications
within a group of devices. In this paper, we propose and analyze different
solutions for supporting the communications between multiple WiFi Direct groups
using Android OS devices. By describing the WiFi Direct standard and the
limitations of the current implementation of the Android WiFi Direct framework,
we present possible solutions to interconnect different groups to create
multi-hop ad hoc networks. Experimental results show that our proposed
approaches are feasible with different overhead in terms of energy consumption
and delay at the gateway node. Additionally, our experimental results
demonstrate the superiority of techniques that exploit the device ability to
maintain simultaneous physical connections to multiple groups.
