hash stringlengths 32 32 | doc_id stringlengths 7 13 | section stringlengths 3 121 | content stringlengths 0 2.2M |
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4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.1.2 Fast Forward H.264/AVC picture discarding before decoding | H.264/AVC pictures that are not referenced by other pictures may be discarded prior to decoding to play faster than 1x. H.264/AVC picture references are hierarchical, so discarding the highest reference tier removes dependencies on the next tier so that they may also be discarded. ISO Media files only identify independ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.1.3 Fast forward I picture access | For very fast forward, all but I pictures may be discarded before decoding. If I pictures are repeated once per second, the playback speed would be 50x for 50 Hz frame display rate. That is probably not a sustainable Segment download rate. Decoded I frames may be repeated on output to produce lower speed increases, but... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.1.4 Fast reverse I picture access | Since I pictures are independently decodable, a player can play downloaded Segments in reverse order by parsing the movie fragment box ('moof') to locate I pictures and decode them in reverse order. The frequency of I pictures encoded and refresh duration of each decoded frame will determine the rate of reverse play. I... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.1.5 Segment random access | Segments that are available according to the MPD@type="static", @availabilityStartTime, PVR buffer duration, current UTC time or Segment Timeline are normally requested and played from the start (first IDR picture). DASH Segments are optimized for simple concatenation and decoding, even when sequenced from different Re... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.1.6 Partial Segment fast forward or reverse | ISO Media Segments require movie fragment header information, such as sample byte offsets, to locate and decode media samples (i.e. pictures, TTML documents, and audio sync frames). Video decoding can always start on the first sample of a DASH Segment because it is an IDR picture (it may not be presented first, but it ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.2 Content enabled Trick Modes: | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.2.0 Introduction to Content enabled Trick Modes | The trick play modes listed above do not require special content authoring or MPD description. This clause describes trick play modes that depend on special content and MPD authoring. For instance, including the @maxPlayoutRate attribute in MPDs for lower resolution Representations does not require special content prep... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.2.1 Trick Play Representations | Trick Play Representations consist of long duration Segments containing only H.264/AVC IDR pictures that are typically low frame rate and low resolution to make Segments comparable to normal Segment size and download speed. For example, a Segment duration could be one minute containing sixty 1 Hz images. In this case, ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.6.2.2 Sub Representations | If a specific Representation or SubRepresentation element includes the @maxPlayoutRate attribute, then the corresponding Representation or Sub-Representation may be used for the fast-forward trick mode followed by periodic frame dropping to prevent exceeding the display refresh frequency. The client may play the Repres... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.7 Player Buffering | The Player should not buffer more data than equivalent to approximately 300 seconds of normal play in advance of the current play position. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8 Player Resiliency | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.1 Introduction (informative) | Broadcasters generally go to great lengths to ensure that their output is reliable - in a broadcast environment this involves making use of multiple paths between operational sites, redundant equipment, and controls to automatically switch between these if a failure is detected. They can then provide a highly available... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.2 Handling of BaseURLs by Players | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.2.1 Use of BaseURLs and new attributes | According to ISO/IEC 23009-1 [1], MPDs may contain BaseURLs at many levels (within the MPD, Period, AdaptationSet and Representation elements). At each of these levels there can be more than one BaseURL. The presence of multiple BaseURLs at any given level indicates that the same content can be obtained from more than ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.2.2 Selection of BaseURL | When a Player needs to use a BaseURL to resolve a reference to external content, such as may be found inside a Segment Template, it shall pick the BaseURL as follows: • It shall begin by taking the set of resolved BaseURLs present or inherited at the current position in the MPD, resolved and filtered as described in cl... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.2.3 Changing BaseURL | At any point where a Player needs to change BaseURL as directed in clause 10.8.6, the Player shall: • Add the @serviceLocation attribute value to the blacklist. This BaseURL is removed from the list of available BaseURLs, as are any other BaseURLs in the list with the same @priority attribute value. • Select the set of... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.2.4 BaseURL Example (informative) | Take the following MPD excerpt as an example: Initially the Player has an empty serviceLocation blacklist. When the Player needs to access the media within period "p1" it will resolve the BaseURL within the period element and end up with the following set of BaseURLs: Note that the BaseURL with serviceLocation "D" has ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.3 DNS - HTTP Player | DNS records for a given hostname may provide more than one address. Players should be able to make use of at least one additional address in the event that the first address received in the response is unreachable or refuses connections. ETSI ETSI TS 103 285 V1.3.1 (2020-02) 75 |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4 Types of error condition and recovery options (informative) | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4.0 Introduction | There are a number of types of error condition which may lead to problems. It may not necessarily be obvious which has occurred, but by grouping them into categories a strategy for dealing with each category can be used. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4.1 Heavy server load | Network congestion in the home or the Player's ISP is not an error condition and also is something which adaptive streaming is designed to work around. However congestion at the server end, or servers suffering from high loading, may be avoidable if alternative servers with more available capacity can be used. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4.2 Configuration errors | These types of error may appear when MPDs incorrectly contain links to CDNs which have not been configured to serve the content within the MPD or which have lost connectivity with the content provider. Although this is a situation which should not happen, the possibility needs to be taken into account. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4.3 Authentication errors | Authentication errors could occur for these reasons: • By mistake - for example as a configuration error. • Intentionally - for example a GeoIP check failing. • A time limited token having expired. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4.4 Missing segments | Three problems are collated here as missing segments, however the causes are significantly different and so the response to such errors needs care to avoid causing additional problems. Problems which may lead to segments being irretrievable are: • Equipment failure at the content provider, leading to media segments fro... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4.5 Miscellaneous request errors | There are some HTTP statuses which indicate an error, but are not expected to be encountered. If they are encountered and the Player is unaware of why it has happened then they should be treated in the same way as a configuration error. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.4.6 Transient connection errors or congestion | This category covers errors which lead to dropped or stalled connections, without an identified cause and which do not recur if the connection is reopened. It also covers erratic data transfer caused by congestion. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.5 Specific errors and their categories | This clause lists errors as they are likely to be seen at a Player and the category they belong in. For descriptions of the categories see clause 10.8.4. Player behaviour is defined in clause 10.8.6. ETSI ETSI TS 103 285 V1.3.1 (2020-02) 76 Table 28: Specific errors and their categories Connection HTTP Status Code Erro... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.8.6 Requirements on Players | Where Players encounter an error identified in clause 10.8.4 as being in one of the categories described in clause 10.8.5 then they need to take action to try to enable them to continue. This clause gives some mandatory requirements to ensure that failover between BaseURLs happens in the event of a failure, and to avoi... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9 Live Services | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.1 Overview (informative) | Live services in DASH are provided through the use of mechanisms in the MPD to allow the signalling of availability times and the media segments being short files which can be encoded and then made available over HTTP. The Player retrieves these when they become available according to the MPD. See also ISO 8601 [29] fo... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.2 Determining that an MPD represents a live service | MPEG DASH defines two types of Media Presentations: static and dynamic. A static Media Presentation has all the segments available at the value of the MPD@availabilityStartTime attribute whilst a dynamic media presentation has the segments available over time. ETSI ETSI TS 103 285 V1.3.1 (2020-02) 78 By default, an MPD... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.3 Presentations using segment templates and no segment timeline | Where segments are identified using a segment template using the $Number$ replacement with a constant segment duration, the Player may generate segment names up to the time at which the MPD is to be next be updated (according to the MPD@minimumUpdatePeriod attribute). However not all these segments will be available on... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.4 Considerations for 24/7 operation of a live stream | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.4.0 Introduction | Where live television channels are carried over DASH, the stream may run continuously without Periods or any total duration or end time ever being signalled. This does not pose any conceptual problems for a DASH system, but there may be areas to be considered. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.4.1 AvailabilityStartTime | The availability start time could be a considerable time in the past. Players need to be aware of this possibility. Players shall support availability start times at least one year in the past. This field in the MPD uses the XML Period type, which indicates a time using the UTC format. The MPD time does not track leap ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.4.2 Large segment numbers | For a continuously running stream it is highly likely that segment numbers may become very large. When using segment templates with leading zeroes, these may be quite long. Players shall support segment numbers of at least 10 decimal digits. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.4.3 Large track fragment decode times | Track fragment decode times, particularly for large track timescale values, are likely to require the use of 64 bit values. Therefore Players shall support track fragment decode time using 64 bit numbers. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.9.5 MPD update timing | When playing an MPEG DASH presentation using a dynamic MPD for which minimumUpdatePeriod is defined and there is no InbandEventStream carrying MPD expiration events (see clause 9.1.4), DASH players should request updated MPDs at the minimum rate necessary for correct operation (see clause A.2 of ISO/IEC 23009-1 [1] for... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.12.3.3 Additional attributes on the Reporting descriptor | The following are in the DVB schema to provide additional attributes required by this metric reporting scheme: <xs:attribute name="probability" type="ReportingProbabilityType" use="optional" default="1000"/> <xs:attribute name="reportingUrl" type="ReportingURLType"/> <xs:simpleType name="ReportingProbabilityType"> <xs:... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.12.3.4 Use of the @probability attribute | The DVB reporting mechanism allows sampling of the Player population. This enables content providers to reduce the amount of infrastructure required for handling reports, whilst still obtaining enough data to identify and resolve problems. The sampling is enabled through the use of the probability attribute on the Repo... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.12.3.5 Reporting metrics | This reporting mechanism operates by creating one HTTP GET request for every entry in the top level list of the metric. For example if the metric being reported is "DVB Errors" (see clause 10.8.4) then one GET request is issued for each Entry in the list (with each entry being an individual error). ETSI ETSI TS 103 285... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.20.7.1 Introduction (informative) | A good user experience when joining a live stream depends on content being presented without significant delay when the stream is first selected. When joining a stream, a player has to start decoding from a random access point. In the DVB profile of MPEG DASH, random access points are present at the start of each media... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.20.7.2 Factors affecting start-up delay and latency (informative) | The time taken to begin presenting a stream, and the latency that will be achieved once playback starts, are influenced by the segment duration (and hence the frequency of random access points in the stream) together with the speed at which the player can decode from the random access point to a desired starting frame.... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.20.7.3 Video decoding speed | Two factors influence how fast a video decoder can decode a particular video Representation: • The margin between the content's decoding complexity and the profile and level of the player's decoder. Information about this margin can be carried in a DASH MPD using the @maxPlayoutRate attribute. • The proportion of non-r... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.20.7.4 Start-up delay requirements | Table 34 defines the maximum start-up delay allowed for low latency players to begin presentation of a live stream, defined in terms of the video segment duration Ds, the video chunk duration Dc and a video decoding speed multiple N. The requirements apply where: • There is a video representation of 704x396 resolution ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 10.20.7.5 Latency at start-up | Due to the requirements on start-up delay, the initial latency may vary (within any minimum/maximum latencies) depending on the time that the user joined the stream with respect to the pattern of video segments. Players that support variable speed playback (see clause 10.20.6) may use this capability to adjust the late... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11 Content Provider Guidelines (informative) | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.1 Use of Profiles | All Representations that are intended to be decoded and presented by a DVB conformant Player should be such that they will be inferred to have an @profiles attribute that includes one or more of the profile names defined in clause 4.1, as well as either the one defined in clause 4.2.5 or the one defined in clause 4.2.8... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.2 Video Resolutions and Frame Rates in Adaptation Sets | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.2.0 Introduction | A content provider can choose any number of representations using any video resolution and frames per second within an adaptation set. This clause provides some guidance to help the content provider choose which would be preferable sets of video resolution and frames per second, and the tradeoffs. Adaptive Bit Rate pre... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.2.1 Video Resolutions | It is recommended that the resolutions for progressive representations are taken from the list in Table 35. The table is aimed at several types of devices and connectivity, so content providers may want to restrict the lower horizontal and vertical resolutions if they are delivering to a Connected TV connected by high ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.2.2 Frame Rates | A Content Provider should check the capabilities of the device population as the capabilities of phones and tablets may not be able to display high resolution at high frame rates. This means a Content provider should either provide: • Two representations, one at the artistically chosen fps, and the other for devices th... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.3 Considerations for Audio in Adaptation Sets | 11.3.0 Recommendation for Audio as a Percentage of Total Stream Bandwidth If the service being delivered is a video service, then audio should be 20 % or less of the total stream bandwidth, exceptions to this recommendation can occur at very low video bit rates (e.g. in a mobile environment) or when then audio is the p... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.3.1 Considerations for Advanced Audio Coding | This clause provides additional guidelines for Advanced Audio Coding (AAC) including the selection of AAC Profiles and typical bit rates. It also covers considerations on backward compatibility. It should be noted, that those guidelines are informal recommendations which can be adapted to fit the need of a particular D... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.3.2 Considerations for Enhanced AC-3 and AC-4 | Enhanced AC-3 decoders will decode all bitstreams at valid bit rates and with channel configurations as constrained by ETSI TS 102 366 [10]. AC-4 decoders will decode all bitstreams at valid bit rates and with channel configurations as constrained by ETSI TS 103 190-1 [23]. The number of available playback channels wil... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.3.3 Considerations for DTS Audio Formats | This clause provides additional guidelines for the DTS family of codecs. The DTS family of codecs includes a number of constant bit rate (CBR) coding modes, a "core + lossless" mode and lossless only (VBR) coding modes. It also supports 96 kHz sampling frequency in both lossy and lossless modes, and 192 kHz audio in lo... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.5 Mixing HD and SD in Adaptation Sets | It is recommended that if the master is in HD with Recommendation ITU-R BT.709 [21] colour then this is used to make a lower "SD" resolution set of representations distributed via MPEG-DASH. An SD only capable display device will then take the "SD" resolution version and display it as SD. This allows a single adaptatio... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.6 Mixing H.264/AVC and HEVC in Adaptation Sets | The mixing of HEVC and H.264/AVC in the same adaptation set is not allowed (see clause 4.3). The Content Author can include separate Adaptation Sets for AVC and HEVC in the same MPD to allow support of devices that have HEVC, H.264/AVC or both. |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.7 Subtitles | Subtitles carried according to the present document are carried within EBU-TT-D documents encapsulated within ISO BMFF containers. This provides a mechanism through which both live and on-demand subtitles can be accommodated. Content providers may wish to use media segments for subtitles which have a duration greater t... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.8 Audio/Video Switching Across Period Boundaries | Content Providers should prepare content to ensure that the adaptation set on both sides of the periods have the correct properties if they want seamless switching to happen. ETSI ETSI TS 103 285 V1.3.1 (2020-02) 103 |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.9 Signalling multiple serving locations using BaseURLs | |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.9.1 Introduction | The present document contains a number of requirements on Players in clause 10.8.2 to enable content providers to control the way Players make use of BaseURLs, including a provision for load balancing, and to require automatic failover between different BaseURLs where the signalling indicates this is available. These f... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.9.2 Prioritizing BaseURLs | BaseURLs containing absolute URLs can be assigned a priority using the @priority attribute. The value of this is a positive integer, with the lowest value indicating the highest priority. This allows additional BaseURLs to be specified to improve the reliability of a service, but on the basis that some of the BaseURLs ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.9.3 Load balancing | Load balancing can often be carried out using either equipment in the network, or DNS load balancing. However such mechanisms may not be ideal for balancing between different hosting locations or CDNs, or where the load needs to be distributed in non-equal ratios. A facility for load balancing is provided in clause 10.... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.9.4 Combining priority and load balancing | The failover options described in clause 11.9.2 and the load balancing described in clause 11.9.3 can be combined to provide a fully specified set of load balancing and failover rules. To assist with this the @serviceLocation attribute is used to indicate when BaseURLs share the same hosting platform and should not be ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.9.5 Relative and Absolute BaseURLs | According to ISO/IEC 23009-1 [1], BaseURLs can be carried at a number of levels within an MPD, and may contain both absolute and relative URLs, with relative URLs being resolved either against an absolute URL contained within a BaseURL at a higher level within an MPD or the base URI of the MPD itself. In order to impro... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.17.2.1 Audio Bundle | In the context of next generation audio, an audio bundle is a set of audio programme components that can contribute to the playout of one next generation audio decoder. Examples for audio programme components are an English dialogue, German dialogue, or Music & Effects. The referred audio programme components can be ca... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.17.2.2 Preselection | A Preselection is a set of audio programme components representing a version of the Programme that may be selected by a user for simultaneous decoding. An audio Preselection is a sub-selection from all available audio programme components of one Programme. An audio Preselection may be considered the next generation aud... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.18.2.1 Segment information in the MPD | When content is presented with low latency, there is limited time available to respond to delayed responses to requests for media segments and MPD updates. In order to achieve the best possible reliability, it is recommended that content intended for low latency presentation be produced such that the player does not ha... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.18.2.2 Video chunk duration | A smaller video chunk duration allows smaller units of video to be made available to the client. However, frame re- ordering by the video codec means that there is little benefit in choosing a video chunk duration that is less than the maximum frame re-ordering distance (generally equal to the P-frame distance). ETSI E... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.18.2.3 Audio chunk duration | As audio codecs generally have more frequent random access points and little decoding delay, the considerations for video chunks do not apply. However, in the audio case, very small chunks may not be flushed through network buffers and caches quickly. It is recommended that the audio chunk duration matches that of the ... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.18.2.4 Time synchronisation | Low latency content should include a UTCTiming element that provides a time reference with sub-second accuracy and a LeapSecondInformation element providing correction for leap seconds. When the timing of a future leap second becomes known, the LeapSecondInformation element should be updated to include @nextLeapChangeT... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.18.2.5 Content availability | At the stated availability time of segments and chunks, clients need to be able to request the segment and receive a valid response. If the content encoding, packaging and distribution chain is such that there may be variable delays in chunk availability, this should be handled in one of two ways: • the availability ti... |
4b4fc3ef15bd130cba301739db0df1c6 | 103 285 | 11.18.2.6 Inband events | Where inband events are being delivered in a low latency stream there are a number of options which comply with the placement rules of clause 5.10.3.3.1 of ISO/IEC 23009-1 [1]: • Where the events themselves do not need to be delivered with low latency, emsg boxes can be inserted only at the beginning of segments, as no... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 1 Scope | The present document defines classes of Emergency Communication Cell over Satellite (ECCS) devices [i.1]. An ECCS device provides short to medium range communication capabilities to emergency responders using terrestrial technologies. In addition, the ECCS device interconnects (backhauls) these terrestrial technologies... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 2 References | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the referenced document (including any amendments) applies. Referenced documents which a... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 2.1 Normative references | The following referenced documents are necessary for the application of the present document. [1] IEC 60529: "Degrees of protection provided by enclosures (IP Code)". [2] IEEE 802.11: "IEEE Standard for Information technology - Telecommunications and information exchange between systems Local and metropolitan area netw... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 2.2 Informative references | The following referenced documents are not necessary for the application of the present document but they assist the user with regard to a particular subject area. [i.1] ETSI TR 103 166 (V1.1.1): "Satellite Earth Stations and Systems (SES); Satellite Emergency Communications (SatEC); Emergency Communication Cell over S... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 3 Abbreviations | For the purposes of the present document, the following abbreviations apply: DECT Digital Enhanced Cordless Telecommunications dPMR Digital Private Mobile Radio ECCS Emergency Communication Cell over Satellite GNSS Global Navigation Satellite Systems IATA International Air Transport Association PLMN Public Land Mobile ... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 4 Classes of ECCS devices | An ECCS device provides a temporary emergency communication cell supporting terrestrial wireless and wired standard(s) which are linked/backhauled to a permanent infrastructure by means of bi-directional satellite links [i.1]. The present document does not make any assumption of the satellite access technology that is ... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 4.1 Rationale | The present clause refers to three classes of ECCS devices called "pocket", "portable" and "transportable" that are defined in clause 4.2. These classes are sorted by increasing form factor, communication capabilities and likely cost of manufacturing. The rationale of having multiple classes is to achieve the best fitn... |
2645c901adfaedd7a7270ba960a7d0b0 | 103 284 | 4.2 Classes | Three classes are defined: "pocket ECCS", "portable ECCS" and "transportable ECCS". Table 1 lists the correspondence among these classes and the communication capabilities, interconnection capabilities and usage aspects. Table 1: Communication capabilities, interconnection capabilities and usage aspects for classes A, ... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 1 Scope | The result of the European Commission Study Group on Smart Appliances ontologies takes into account all the interest of the relevant stakeholders. The present document is an adaptation of the reviewed study to the structure of a normative deliverable. Additionally, it develops the mapping to oneM2M. Therefore the prese... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 2 References | |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 2.1 Normative references | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. Referenced documents which ar... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 2.2 Informative references | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. NOTE: While any hyperlinks in... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 3 Definitions and abbreviations | |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 3.1 Definitions | For the purposes of the present document, the following terms and definitions apply: ontology: formal specification of a conceptualization, used to explicitly capture the semantics of a certain reality smart appliances: devices, which are used in the household, e.g. for performing domestic work, and which have the abil... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: CECED European Committee of Domestic Equipment Manufacturers CENELEC European Committee for Electrotechnical Standardization DUL DOLCE+DnS Ultralite EC European Commission eu.bac European building automation controls association FAN FlexiblePo... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 4 Smart Appliances reference ontology and semantics | |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 4.1 Introduction and overview | A study on "Available Semantics Assets for the Interoperability of Smart Appliances: Mapping into a Common Ontology as a M2M Application Layer Semantics" had been tendered by the European Commission and was carried out by TNO. Parts of the final report of this study [1] are copied to clauses 4.1 to 4.4. The energy util... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 4.2 Principles | The Smart Appliances REFerence ontology (SAREF) is conceived as a shared model of consensus that facilitates the matching of existing assets in the smart appliances domain, reducing the effort of translating from one asset to another, since SAREF requires one set of mappings to each asset, instead of a dedicated set of... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 4.3 SAREF | SAREF focuses on the concept of device, which is defined in the context of the Smart Appliances study as "a tangible object designed to accomplish a particular task in households, common public buildings or offices. In order to accomplish this task, the device performs one or more functions". Examples of devices are a ... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 4.4 Observations about SAREF | SAREF currently does not contain explicit references to upper ontologies such as DUL or SUMO. The use of upper ontologies is a best practice in ontology engineering , but the smart appliances industry - main user of SAREF - is very pragmatic and is not acquainted with high-level upper ontologies. Introducing DUL would ... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 4.5 Extensions of SAREF | The goal of the present document is to have a system, in which SAREF can be used, e.g. for conformance tests of SAREF. The horizontal oneM2M architecture (as the follow-up system of the ETSI M2M architecture) is chosen as a system to be used with SAREF in order to facilitate the communication between the Smart Applianc... |
939fea02fdd12266abd6a8d09167e73a | 103 264 | 5 Mapping on oneM2M resources | NOTE 1: This clause describes how ETSI SAREF is to be used with the oneM2M architecture. The idea is to map ETSI SAREF to the oneM2M base ontology. For the oneM2M base ontology, oneM2M is in the process of defining mapping rules that map some key concepts to oneM2M resources, e.g. creating an Application Entity resourc... |
48f0d2d4386f1a3ae1c298104f4cb09f | 103 280 | 1 Scope | The present document defines a dictionary of parameters that are commonly used in multiple TC LI specifications. Aside from defining a dictionary, the present document aims to provide technical means for other specifications to use. It is encouraged to use the present document in the development of new specifications. ... |
48f0d2d4386f1a3ae1c298104f4cb09f | 103 280 | 2 References | |
48f0d2d4386f1a3ae1c298104f4cb09f | 103 280 | 2.1 Normative references | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the referenced document (including any amendments) applies. Referenced documents which a... |
48f0d2d4386f1a3ae1c298104f4cb09f | 103 280 | 2.2 Informative references | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the referenced document (including any amendments) applies. NOTE: While any hyperlinks i... |
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