Social sensing services use humans as sensor carriers, sensor operators and sensors themselves in order to provide situation-awareness to applications. is promises to provide a multitude of bene ts to the users, for example in the management of natural disasters or in community empowerment. However, current social sensing services depend on Internet connectivity since the services are deployed on central Cloud platforms. In many circumstances, Internet connectivity is constrained, for instance when a natural disaster causes Internet outages or when people do not have Internet access due to economical reasons. In this paper, we propose the emerging Fog Computing infrastructure to become a key-enabler of social sensing services in situations of constrained Internet connectivity. To this end, we develop a generic architecture and API of Fogenabled social sensing services. We exemplify the usage of the proposed social sensing architecture on a number of concrete use cases from two di erent scenarios. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for pro t or commercial advantage and that copies bear this notice and the full citation on the rst page. Copyrights for components of this work owned by others than the author(s) must be honored. Abstracting with credit is permi ed. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior speci c permission and/or a fee. Request permissions from permissions@acm.org.
CCS CONCEPTS
SOCIAL SENSINGSituation-aware applications use data streams from sensors to provide useful services to users or other applications. With the proliferation of sensors deployed in the surrounding world, e.g., through the Internet of ings, the potential of such applications is reaching new dimensions. Recently, research focus has been expanded from traditional xed sensor deployments toward social sensing [1]. is comprises passive sensors provided by human carriers in Smart Phones, active human sensor operators taking pictures or videos and even humans operating as sensors themselves, e.g., providing live information in tweets and postings. Recently, new applications have been proposed which use the social sensing infrastructure to infer situations that are not detectable from traditional sensors.
Application FieldsAn important application eld of social sensing is in helping people to deal with natural disasters. ere are applications that help in nding friends and family in the a ermath of a natural disaster [19]. Furthermore, social media can provide access to relevant and timely information to individuals in a ected regions [17]. Providing real-time information to disaster-a ected people about the situation in the area can help them take mitigative actions, for instance moving contents located in a ood-prone ground oor to upper oor [2] to reduce the loss caused by the disaster. Social media has been an e ective way of sharing this...