Location and Time Data Source --> Transit Vehicle OBE:
location and time
Definitions
location and time (Information Flow): The current geographic location in three dimensions (latitude, longitude, elevation) and the current time.
Location and Time Data Source (Source Physical Object): The 'Location and Time Data Source' provides accurate position information. While a Global Positioning System (GPS) Receiver is the most common implementation, this physical object represents any technology that provides a position fix in three dimensions and time with sufficient accuracy.
Transit Vehicle OBE (Destination Physical Object): The 'Transit Vehicle On-Board Equipment' (OBE) resides in a transit vehicle and provides the sensory, processing, storage, and communications functions necessary to support safe and efficient movement of passengers. The types of transit vehicles containing this physical object include buses, paratransit vehicles, light rail vehicles, other vehicles designed to carry passengers, and supervisory vehicles. It collects ridership levels and supports electronic fare collection. It supports a traffic signal prioritization function that communicates with the roadside physical object to improve on-schedule performance. Automated vehicle location enhances the information available to the transit operator enabling more efficient operations. On-board sensors support transit vehicle maintenance. The physical object supports on-board security and safety monitoring. This monitoring includes transit user or vehicle operator activated alarms (silent or audible), as well as surveillance and sensor equipment. The surveillance equipment includes video (e.g. CCTV cameras), audio systems and/or event recorder systems. It also furnishes travelers with real-time travel information, continuously updated schedules, transfer options, routes, and fares. A separate 'Vehicle OBE' physical object supports the general vehicle safety and driver information capabilities that apply to all vehicles, including transit vehicles. The Transit Vehicle OBE supplements these general capabilities with capabilities that are specific to transit vehicles.
Included In
This Triple is in the following Service Packages:
This triple is associated with the following Functional Objects:
This Triple is described by the following Functional View Data Flows:
This Triple has the following triple relationships:
None |
Communication Solutions
- GNSS Data - GNSS serial interface (6)
Selected Solution
Solution Description
ITS Application Entity
NMEA 0183 |
Click gap icons for more info.
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Mgmt
No Standard Needed |
Facilities
No Standard Needed |
Security
No Standard Needed |
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TransNet
NMEA 0183 |
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Access
NMEA 0183 |
Note that some layers might have alternatives, in which case all of the gap icons associated with every alternative may be shown on the diagram, but the solution severity calculations (and resulting ordering of solutions) includes only the issues associated with the default (i.e., best, least severe) alternative.
Characteristics
Characteristic | Value |
---|---|
Time Context | Now |
Spatial Context | Adjacent |
Acknowledgement | False |
Cardinality | Broadcast |
Initiator | Source |
Authenticable | True |
Encrypt | True |
Interoperability | Description |
---|---|
Local | In cases where an interface is normally encapsulated by a single stakeholder, interoperability is still desirable, but the motive is vendor independence and the efficiencies and choices that an open standards-based interface provides. |
Security
Information Flow Security | ||||
---|---|---|---|---|
Confidentiality | Integrity | Availability | ||
Rating | Moderate | High | High | |
Basis | While time reference should be universally available, time reference coupled with vehicle location is tracking data. This flow is internal to a vehicle, but should probably be encrypted to discourage hacking and snooping on the vehicle bus. Thus MODERATE. | Location and time data is the basis for crash imminent safety and a host of other applications. Corruption of this flow could lead directly to a vehicle accident. | If this information is not available, crash imminent safety applications depending on this information will not function properly. |
Security Characteristics | Value |
---|---|
Authenticable | True |
Encrypt | True |