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SAE J2735-Draft-Rev26 [issued: 09-18-08]
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This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
3.47 lane: In the context of this standard a lane is a portion of the transportation network (typically a
section of roadway geometry) which is being described (its paths and various attributes about it) or referred
to. In the DSRC message set, the lane object is widely used. Lanes consist not only of sections of
“drivable” roadway trasversed by motor vehicles, but other types of lanes including pedestrian and bicycle
walkways, trains and transit lanes, and certain types of dividers and barriers. When used in describing an
intersection, a lane is defined for each possible path into and out of the intersection (in the MAP message),
and the current signal phase (and therefore the allowed movements) then applicable to that lane or its
approach is provided in the SPAT message.
3.48 lane-use control signal: A signal face displaying signal indications to permit or prohibit the use of
specific lanes of a roadway or to indicate the impending prohibition of such use.
3.49 link: A service channel being used in support of application data transfer needs.
3.50 management plane: The collection of functions performed in support of the communication system
operation, but not directly involved in passing application data.
3.51 message: A well structured set of data elements and data frame that can be sent as a unit between
devices to convey some semantic meaning in the context of the applications about which this standard
deals.
3.52 message set: A collection of messages based on the ITS functional-area they pertain to. This DSRC
standard is also a message set.
3.53 message set extender: The concept of a message set extender refers to the process of adding
additional data elements to a common (non-changing) core message in order to extend the basic core
message structure to create messages for specific applications needs.
3.54 metadata: Data that defines and describes other data.
3.55 networking services: The collection of management plane and data plane function at the network
layer and transport layer, supporting WAVE communications.
3.56 Node Configuration data: Definition to be refined by committee. When a map of an intersections is
represented a node configuration data value provided key information regarding how the data vales found
in the map are to be understood.
3.57 notification: An indication of an event of interest, sent to an application.
3.58 OBU to vehicle host interface (OVHI): Interface on the OBU offering access to WAVE capabilities
by other vehicle-based devices.
3.59 offset (phase): Offset is the time lag for the cycle start of a coordinated signal. Quoting from the
FHWA Signal Timing Manual, Chapter 6, Section 6.1 Terminology. (Draft 3 version, development still
underway): “The time relationship between coordinated phases defined reference point and a defined
master reference (master clock or sync pulse)." In other words, a local signal controller setting that
references the start of the green to a common clock so the beginning of green can be coordinated along a
roadway to speed motorist along at a designed speed.
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