Information Technology Reference
In-Depth Information
An overview of the architecture of the EIMS is depicted in Fig. 2 highlighting
the key EIMS Managers and its main interfaces. Note however, that due to space
constraints it is not possible to describe in detail every EIMS Manager and every
interface shown in the figure and, thus, for further details the interested reader is
referred to [12].
The different EIMS subsystems cooperate among them, implementing func-
tionality to:
•
receive and process user requests, contacting various sources of content to find
useful results for the user queries;
•
determining the restrictions imposed by the context of usage by collecting rele-
vant contextual metadata;
•
selecting the best source(s) of content which are able to provide the content in a
format that suits the sensed restrictions;
•
determine the actual service parameters to pass to the source of the content; and
•
subscribing to the required resources to support the selected service.
3.2 End-to-End QoS Manager
The aim of the End-to-End QoS Manager (E2E-QoS-Mngr) is to provide the best
Digital Item configuration towards the content consumer taking into account vari-
ous information coming from different business actors along the delivery chain.
This information is ideally represented as MPEG-21 compliant metadata and en-
capsulated within the Digital Item Declaration which will be configured according
to the requirements of the content consumer. The various metadata assets are
briefly described in the following:
•
The
Digital Item Declaration (DID)
comprising the content variations from
which the E2E-QoS-Mngr may choose. The DID provides a representation of
the Digital Item compliant to MPEG-21 Part 2 [13] and is usually provided by
the content provider (CP).
•
The characteristics of the available television and multimedia (TVM) proces-
sors which may be selected by the E2E-QoS-Mngr based on the network char-
acteristics or conditions (i.e., the information from the provider-to-provider
Service Level Specification (pSLS)) between the content consumer and the
various TVMs. The TVMs are described by a unified description model featur-
ing MPEG-7 and MPEG-21 tools and is generally referred to as TVM Resource
Function (TVMRF) [14].
•
The capabilities and network information from the terminal of the content con-
sumer, including the class of service for the requested multimedia service. This kind
of information is described in a format compliant to MPEG-21 DIA UED tools.
The E2E-QoS-Mngr implements a process of automated construction of a possibly
suitable sequence of TVMs for a given set of multimedia content variations and a
set of environmental requirements as described in [15].
