SANY D2.3.4 Specification of the Sensor Service Architecture V3 Doc.V3.1
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4.1.4 Evolutionary Development - Design for Change
The SensorSA shall be designed to evolve, i.e. it shall be possible to develop and deploy the system  in  an  evolutionary  way.  The  SensorSA  shall  be  able  to  cope  with  changes  of  user
requirements,  system  requirements,  organisational  structures,  information  flows  and information types in the source systems.
4.1.5 Component Architecture Independence
The SensorSA shall be designed such that a service network and source systems i.e. existing information systems, sensors and sensor networks are architecturally decoupled. This means
that  the  SensorSA  shall  not  impose  any  architectural  patterns  on  source  systems  for  the purpose of having them collaborate in a service network, and no source system shall impose
architectural patterns on a SensorSA.
Note: This architectural principle relies on the RM-OA definition of a source system as being  a  “container  of  unstructured,  semi-structured  or  structured  data  andor  a  provider  of
functions  in  terms  of  services.  The  source  systems  are  of  a  very  heterogeneous  nature  and c
ontain  information  in  a  variety  of  types  and  formats”.  In  the    context  of  a  sensor  service network,  a  source  system  may  also  be  a  sensor  or  a  sensor  network  to  be  integrated  in  a
service  network.  Important  here  is  that  a  source  system  is  seen  as  a  black  box,  i.e.  no assumptions about its inner structure are made when designing a service network.
4.1.6 Generic Infrastructure
The SensorSA services shall be independent of the application domain. This means that the SensorSA services shall be designed in such a flexible and adaptable way that the SensorSA
services  can  be  used  across  different  thematic  domains  and  in  different  organisational contexts,  and  that  the  update  of  integrated  components  e.g.  sensors,  applications,  systems,
ontologies causes little or ideally no changes to the users of the SensorSA services.
4.2. Relationship to the ORCHESTRA Architecture
The  architectural  heritage  of  the  SensorSA  is  the  ORCHESTRA  Architecture  specified  in RM-
OA, 2007 as an “open architecture that comprises the combined generic and platform- neutral  specification  of  the  information  and  service  viewpoint  as  part  of  the  ORCHESTRA
Reference Model ” RM-OA. Consequently, the SensorSA builds upon the components of the
ORCHESTRA Architecture which comprise:
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Rules  and  guidance  about  how  to  specify  information  and  service  models  in  the context of international standards. In the RM-OA, these rules are formally specified in
an ORCHESTRA Meta-model
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for information and for services.
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The ORCHESTRA Meta-model is an extension of the ISOOGC-defined General Feature Model. It consists of a  set  of  UML  classes  stereotyped  as  MetaClass  and  associated  textual  rules  that  provide  guidance  on  how
application  schemas  and  services  have  to  be  specified  in  UML,  i.e.  on  a  platform-neutral  abstract  level.  It encompasses two parts: one for the specification of information models in the form of application schemas, and
one for the specification of interface and service types.
SANY D2.3.4 Specification of the Sensor Service Architecture V3 Doc.V3.1
Copyright © 2007-2009 SANY Consortium Page 30 of 233
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Basic  re-usable  specification  units  for  information  models  e.g.  pre-defined  feature types
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and service models e.g. re-usable interfaces.
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Textual and document templates that guide the specification of services.
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A series of textual descriptions and formal specifications of generic services so-called ORCHESTRA  Architecture  Services  or,  in  short,  architecture  services  that  are
application- and technology independent.
It  is  the  objective  of  the  SANY  project  to  re-use  and  apply  these  components  in  the context  of  the  SensorSA  to  the  extent  that  they  fulfil  the  requirements  of  building  service
networks
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based on sensor information and higher-level sensor information processing. Thus, there are two cases:
1.  The SensorSA contributes to the architectural level in the sense that it specifies new architectural  concepts  or new architecture services, or it refines existing  architecture
services. 2.  The SensorSA specifies new application-oriented services in the RM-OA categorised
as  ORCHESTRA  Thematic  Services  or,  in  short,  thematic  services  that  typically require  the  call  of  underlying  architecture  service  operations.  In  this  case  the
SensorSA defines a so-called ORCHESTRA Application Architecture
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. In both cases, the SensorSA uses the templates and the rules of the RM-OA in order to
specify the refined and the new components.
4.3. Requirements of GMES