ISO 19080:2016 高度道路交通システム—陸上移動用通信アクセス（CALM）—CoAP施設 | ページ 6

3.1

ITS-S CoAP node

device/node that implements CoAP protocol

[SOURCE: IETF RFC 7252]

3.2

ITS-S CoAP Endpoint

entity participating in the CoAP protocol

Note 1 to entry: Colloquially, an endpoint lives on a “node”, although “host” would be more consistent with Internet standards usage, and is further identified by transport-layer multiplexing information that can include a UDP port number and a security association.

[SOURCE: IETF RFC 7252]

3.3

ITS-S CoAP Client

originating endpoint of a request; the destination endpoint of a response

[SOURCE: IETF RFC 7252]

3.4

ITS-S Server

destination endpoint of a request; the originating endpoint of a response

[SOURCE: IETF RFC 7252]

3.5

confirmable message

message requiring an acknowledgement

Note 1 to entry: These messages are called “confirmable”. When no packets are lost, each confirmable message prompts exactly one return message of type acknowledgement or type reset.

[SOURCE: IETF RFC 7252]

3.6

non-confirmable message

message not requiring an acknowledgement

Note 1 to entry: This is particularly true for messages that are repeated regularly for application requirements, such as repeated readings from a sensor.

[SOURCE: IETF RFC 7252]

3.7

acknowledgement message

message acknowledging that a specific confirmable message arrived

Note 1 to entry: By itself, an acknowledgement message does not indicate success or failure of any request encapsulated in the confirmable message.

[SOURCE: IETF RFC 7252]

3.8

reset message

message indicating that a specific message (confirmable or non-confirmable) was received, but some context is missing to properly process it

Note 1 to entry: This condition is usually caused when the receiving node has rebooted and has forgotten some state that would be required to interpret the message. Provoking a reset message (e.g. by sending an empty confirmable message) is also useful as an inexpensive check of the aliveness of an endpoint (“CoAP ping”).

[SOURCE: IETF RFC 7252]

3.9

subject

resource in the namespace of an ITS-S CoAP server

Note 1 to entry: The state of the resource can change over time, ranging from infrequent updates to continuous state transformations.

[SOURCE: IETF RFC 7641]

3.10

observer

ITS-S CoAP client that is interested in having a current representation of the resource at any given time

[SOURCE: IETF RFC 7641]