Intermodal Mobility Assistance for Megacities - Smart Information Systems: Computational Intelligence for Real-Life Applications - page 350

As an example for an external service, we implemented the Bing Traffic Data
Service . The Real-time Traffic Bean was designed to actively retrieve information
from this service in a 15 min interval, in order to have the latest traffic updates.
Another feature of the Real-time Traffic Bean is its connection to the graphical user
interface. Since communication in multiagent systems is asynchronous, we selected
the WebSocket Protocol (described in RFC6455 by the “Internet Engineering Task
Force” 6 ) for transmitting data between the web-based graphical user interface and
the IMA Routing System. Thus, the Real-time Traffic Bean can be considered as
a web socket server, handling incoming routing requests and actively pushing the
traffic situation whenever it changes.
The actions provided by the OSM Routing Agent can be grouped into two cate-
gories:
•

routing-specific actions, and

• traffic-specific actions.

Capabilities that were implemented for connecting the routing system to the graph-
ical user interface fall in none of these categories.
The category of routing-specific actions contains all actions which facilitate the
separation between the Real-time Traffic Bean and the Plain Routing Bean. Incoming
routing requests are converted and forwarded to the Plain Routing Bean. When the
route has been calculated, it is forwarded to the Real-time Traffic Bean and returned
to the requesting service. Also, the status of the Plain Routing Bean is checked to
ensure that it is fully functional and ready to receive requests.
In compliance with the categories for the Plain Routing Bean actions, routing
actions for the Real-time Traffic Bean can be grouped into the following categories:
• searching the shortest path, and

• searching the fastest path.

The Real-time Traffic Bean does not offer actions for routing without the use of
traffic information, as this is not the purpose of the bean. Traffic-specific actions
offer the interfaces for other services. With these interfaces traffic information may
be pushed to the Real-time Traffic Bean.
Currently the bean provides actions for the Video Analysis agent. We explain this
component below.

13.3.2 The Video Analysis Agent

The Video Analysis ( VA ) component is implemented as a JIAC agent, namely the
Video-Analysis-Agent. The aim of the VA component is to support the routing com-
ponent of the IMA system (i.e., the Real-time Traffic Bean, see Sect. 13.3.1.3 )by
analyzing traffic flow based on video data gathered from traffic surveillance cameras

6

Internet Engineering Task Force website: http://tools.ietf.org/html/rfc6455/ .