Problems and Goals

A great number of people spend one or more hours each day driving between home and the office. These daily roadway commutes are highly predictable and regular, and provide a great opportunity to form virtual mobile communities. However, even though these commuters are already physically present in the same location, they are limited in their ability to communicate with each other. This paper presents a framework for building such communities, which we call as Vehicular Social Networks (VSNs), to facilitate better communication between commuters driving on highways. As a proof of concept, we present the design of RoadSpeak, a VSN-based system which allows drivers to automatically join VSNs along popular highways and roadways, and communicate with each other by means of voice chat messages.

The primary goal of RoadSpeak has been to facilitate better communication between people who are already physically present in the same location, but who are limited in their ability to communicate with each other.


Project Description

Social Networks allow people with common interests to come together and form virtual communities. Mobile Social Networks connect people who are already together (sharing the same locality), enabling them to take advantage of their close proximity
to form more tightly-coupled, possibly even ad-hoc, virtual communities. In this socially-driven virtual world, people can form “instant villages” that mirror and facilitate real-world interaction. Today, services such as Dodgeball [5] utilize mobile phones to exchange information between users regarding their locality to identify opportunities to meet. Friends can find each other when they happen to be close by, and people can find others they have never met who share their interests, as well as, their location. Mobile social networking services are successful primarily because they directly take advantage of the, often periodic, physical locality patterns of the users to improve their knowledge about opportunities to socialize.

A heretofore unexplored source of physical locality, which can be taken advantage of for mobile social networking, is the daily roadway commute. A great number of people, especially in densely populated locales, spend one or more hours each day driving between home and the office. Since these commutes typically take people over highways and other frequented corridors, they are highly predicable and regular. Day after day, the same people travel along the same roadways at the same time. Therefore, the opportunity exists to form periodic virtual mobile communities. We call these virtual communities Vehicular Social Networks.

In our framework, a VSN such as a Voice Chat Group (VCG) is defined by a profile consisting of triplet {time, location, interests}. Aside from interests, on which traditional social networks are formed, VSNs also include time and location in their definition, which may limit membership to specified roads and intervals of time. In RoadSpeak, the VCGs are maintained by a central group manager, although decentralized approaches can also be envisaged. The VCG profile is defined by the group owner (which can be the manager, an organization, or simply a user), when the group is created. Users are admitted to groups based on matching their user profiles to the group’s profile. Admission can be free or it can be restricted by certain requirements,
which the user must prove, such as a location frequency threshold for a specified roadway segment, during a specified time slot. By limiting group membership based on the users’ roadway recurrence frequency, VSN-based groups may be limited to commuters, the best target for this system, rather including than transient travelers. Additionally, time and location properties can be used to provide regularity in a group’s membership, i.e., the same group of people are in contact with each
other on a daily basis with new members only being admitted once they have met the frequency requirement.









Liviu Iftode

Graduate Students

Lu Han, Stephen Smaldone, Pravin Shankar,

Undergraduate Students

James Boyce



Development Toolkits:

Related Projects Commercial Mobile Social Networks


Last Modified July, 2010