  The emergence of connected vehicles paradigm has made secure communication a
key concern amongst the connected vehicles. Communication between the vehicles
and Road Side Units (RSUs) is critical to disseminate message among the
vehicles. We focus on secure message transmission in connected vehicles using
multi_hop social networks environment to deliver the message with varying
trustworthiness. We proposed a Geographic Social Trust Routing (GSTR) approach;
messages are propagated using multiple hops and by considering the various
available users in the vehicular network. GSTR is proposed in an application
perspective with an assumption that the users are socially connected. The users
are selected based on trustworthiness as defined by social connectivity. The
route to send a message is calculated based on the highest trust level of each
node by using the nodes social network connections along the path in the
network. GSTR determines the shortest route using the trusted nodes along the
route for message dissemination. GSTR is made delay tolerant by introducing
message storage in the cloud if a trustworthy node is unavailable to deliver
the message. We compared the proposed approach with Geographic and Traffic Load
based Routing (GTLR), Greedy Perimeter Stateless Routing (GPSR), Trust-based
GPSR (T_GPSR). The performance results obtained show that GSTR ensures
efficient resource utilization, lower packet losses at high vehicle densities.
