Location and Time Data Source --> Center:
location and time

Definition
Included In
Communication Solutions
Characteristics
Security

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.

Center (Destination Physical Object): This general physical object is used to model core capabilities that are common to any center.

Included In

This Triple is in the following Service Packages:

SU05: Location and Time

This triple is associated with the following Functional Objects:

Center Support Services

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)

Solutions are sorted in ascending Gap Severity order. The Gap Severity is the parenthetical number at the end of the solution.

Selected Solution

GNSS Data - GNSS serial interface

Solution Description

This solution is used within Australia, the E.U. and the U.S.. It combines standards associated with GNSS Data with those for GNSS serial interface. The GNSS Data standards include upper-layer standards required to obtain location and time information from a satellite-positioning-system-based geolocation receiver. The GNSS serial interface standards include lower-layer standards that support communications between connected ITS equipment and geolocation equipment such as a GPS receiver.

ITS Application Entity NMEA 0183			Click gap icons for more info.
Mgmt No Standard Needed	Facilities No Standard Needed	Security No Standard Needed
	TransNet NMEA 0183
	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	False

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	Low	High	High
Basis	Time reference and location information for Center systems should be observable. There is no reason to obfuscate.	Location and time data is the basis for safety and a host of other applications.While a center-system is probably not in the critical decision path for safety-related applications, it is likely to be in the critical path for applications that have a significant effect on system wide applications of other types. Considering the wide-ranging impact a corruption in time and or location could have on those applications, a compromise in this flow could have major negative impacts.	If this information is not available, applications depending on this information will not function properly. Given the scope of center-based applications, this flow's availability is of paramount importance.

Security Characteristics	Value
Authenticable	True
Encrypt	False

Location and Time Data Source --> Center:location and time