ISO/IEC TR 29181-6:2013 情報技術—将来のネットワーク—問題の説明と要件—パート6：メディアトランスポート | ページ 6

3.1

data

sequence of octets which is conveyed across the network as a single unit

[SOURCE: ISO/IEC TR 29181-3, 3.1]

3.2

media

sequence of bits in a defined format which encodes physical entities such as images, sounds, and text.

3.3

time-independent media

media where the semantic of the content does not depend upon a presentation according to the time domain

3.4

time-dependent media

media where there exists a temporal relation amongst the media units

3.5

content

media media that is carried in the payload of datagrams sent over the network

3.6

static content

time-independent media that is carried in the payload of datagrams sent over the network

3.7

streamed content

time-dependent media that is carried in the payload of datagrams sent over the network but does not have requirements for latency

3.8

live content

time-dependent media that is carried in the payload of datagrams sent over the network and has requirements for latency.

3.9

encapsulation

additional octets or other symbols associated with a data unit which serve to delimit it or to identify aspects of the service it should receive

[SOURCE: ISO/IEC TR 29181-3, 2.15]

3.10

container

encapsulation structure containing a payload, either data units or content, and the header composed by two parts, what refers to the payload and to the underlying network

Note 1 to entry: Container has attributes as header fields, which some are related to particular services, and others are general and specific for a sort of communication.

3.11

context

set of data or information that completely describes a particular communication environment at a particular point in time

[SOURCE: ISO 16484-5:2007 (Identifier: CDB-00119069-001)]

3.12

context-awareness

ability of a network to be aware of the context and react accordingly in order to adapt either itself or the data conveyed over

3.13

modular paradigm

paradigm where complex functions are composed by well-known and deterministic basic functions

Note 1 to entry: In network realm, protocols are breaking down into its fundamental (also called atomic) functions, such as sequencing, cyclic redundant coding, addressing, and so on, which combined results into complex functions (or protocols).

3.14

MANE (Media Aware Network Element)

content and context aware network element capable of processing media content passing through to accommodate a given content or service according to the context

Note 1 to entry: This element may handle all attributes of containers taking into account the content type and properties, networking properties and status, and other environmental and conditional properties that may have effect in routing of the contents and services.

3.15

quality of service (QoS)

set of qualities related to the collective behaviour of one or more objects

[SOURCE: ITU-T Rec. X.902 │ ISO/IEC 10746-2]

Note 1 to entry: QoS is usually defined regarding to three parameters: bandwidth, delay and error. In conversational communications, bandwidth consumption is related to the chosen technology (although the lower one is desired), the delay has to be bounded to assure conversational interactivity among participants, and should be provided a high error resilience to assure a good data delivery in front of any change on the network.

3.16

quality of experience (QoE)

set of subjective and/or objective qualities related to user perception about consumed media content

Note 1 to entry: QoE is usually referred to how the user perceives the consumed content. QoE is more related to subjective quality estimation rather than objective measurements, although they can be related by different mapping schemes.

3.17

connection-oriented

communication between peer protocol entities by means of a connection or association established by an underlying layer

[SOURCE: ISO/IEC 11582:2002 (Identifier: CDB-00009275-001)]

3.18

connectionless

communication between peer protocol entities by means of an unacknowledged, unidirectional transport mechanism provided by an underlying layer

[SOURCE: ISO/IEC 11582:2002 (Identifier: CDB-00009276-001)]

3.19

layer coding (LC)

coding technique in which the video stream is split into several hierarchical layers consisting of base layer and one or more enhancement layers

3.20

multiple description coding (MDC)

coding technique in which a single media stream is fragmented into multiple substreams which can be delivered over the network in different paths