STREAMS Integrated Intelligent Transport System

STREAMS Integrated Intelligent Transport System is an advanced traffic management system designed to operate on Microsoft Windows XP. Like most advanced traffic management systems, STREAMS is an array of institutional, human, hardware, and software components designed to monitor, control, and manage traffic on streets and highways. Advanced traffic management systems come under the banner of ITS (intelligent transport systems). ITS is an umbrella term referring to the application of information and communications technology to transport operations in order to reduce operating costs, improve safety and maximise the capacity of existing infrastructure. STREAMS provides traffic signal management, incident management, motorway management, vehicle priority, traveller information and parking guidance within a single integrated system. STREAMS is developed by [http://www.transmax.com.au Transmax] . The [http://www.mainroads.qld.gov.au Department of Main Roads] in Queensland, Australia uses STREAMS as its advanced traffic management system.

History

In 1969, the [http://www.mainroads.qld.gov.au Department of Main Roads] installed the first Intelligent Transport System in Australia (located at Surfers Paradise). This included 30 signalised intersections featuring centralised control and traffic responsive capabilities.

In 1985, a second generation traffic management system was installed in Cairns, Australia. This was known as the TRAC System, or Traffic Responsive Adaptive Control System. Progressive installation of the TRAC system followed at several more sites around Queensland including the capital city, Brisbane.

In 1988, a traffic management system was installed for the South East Freeway in Brisbane, Australia. The features included were ramp metering and graphical displays of traffic conditions to allow for incident detection.

In 1998, the TRAC and South East Freeway's systems were merged to create STREAMS Version 1.

In 2004, the division of Main Roads responsible for continuing development of STREAMS was privatised to form [http://www.transmax.com.au Transmax] . The company remains 100% owned by the [http://www.mainroads.qld.gov.au Department of Main Roads] .

Currently, STREAMS is at version 2.92. Approximately 1,500 signalised intersection are managed across 17 installation sites in Queensland, Australia.

The next major release, STREAMS 3.0, is scheduled for 2007. According to Transmax, this release will contain fully adaptive traffic signal management which has been a criticism of previous versions.

The name STREAMS was derived via the association of managing multiple modes or "streams" of traffic (e.g. public transport, private cars, pedestrians, bicycles, and commercial vehicles) as well as the concept of "streams" of data which are inherent in any distributed computing system.

Software Architecture

STREAMS employs a distributed computing software architecture. Field hardware such as intersection controllers, video cameras and speed detectors are connected via field processors back to a central application server. Users connect to the application server via the workstation software. Field communications are via Optical Fibre, DSL, Wireless or PAPL connections.

The software is built in distinct modules for each distinct area of traffic / transport control and monitoring. The workstation software communicates to the application server software via a publisher / subscriber model (i.e. workstations subscribe to specifically requested streams of data which are published by the application server).

The software architecture model is designed to support the software's claim of being an "integrated" Advanced Traffic Management System. This breaks away from the inter-operability model, which is multiple ITS systems working in parallel, each performing a discrete function.

The workstation software is built around a central user interface called "STREAMS Explorer". Other specification / reporting applications can all be launched from STREAMS Explorer.

The transport network data is set up via a GIS (Geographic Information System). The GIS allows for a graphical user interface displaying transport network data overlaid on street maps and updating in real-time.

The application server uses a Microsoft SQL Server 2000 database running on Microsoft Windows Server 2003. Linux is employed as the operating system for all field processors. The workstation software is designed to run on Microsoft Windows XP Professional. For security reasons, STREAMS employs 128-bit SSL encryption across all data and communication links. As well, firewalls, intrusion detection systems, and authorisation mechanisms are utilised.

Criticism

STREAMS has been criticised by competing systems such as SCATS for the lack of true adaptive traffic capabilities. SCATS employs a method of automatically modifying traffic plans in real-time to optimise traffic flow. STREAMS does not generate its own traffic plans, but instead allows for dynamic operation in which the system can choose the optimal traffic plan from a selection of plans created by users.

See also

* Advanced Traffic Management System
* Intelligent Transport Systems
* SCATS
* BLISS
* Geographic Information System

External links

* [http://www.transmax.com.au Transmax]
* [http://www.mainroads.qld.gov.au/ Department of Main Roads]