Project Name

System and Service Architecture
ESA Template Ver.2.1, Issue date: 14Feb2018

Approval

Title: System and Service Architecture
Issue Number: / Revision Number:
Author(s): / Date:
Approved by: / Date of Approval:

Change Log

Reason for change / Issue / Revision / Date

Change Record

Issue Number: / Revision Number:
Reason for change / Date / Pages / Paragraph(s)

Distribution

Name/Organisational Unit:

Table of contents:

1Introduction

2Overall System Architecture

3Design and Development Plan

4Design Justification File

Design Justification Form #1 - Item or area concerned

Design Justification Form #2 - Item or area concerned

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1Introduction

1.1Reference Documents

Ref. / Document ID. / Title / Rev.

1.2Acronyms

Tag / Description
SSA / System and Service Architecture

2System/SERVICE Architecture

This section shall include a presentation of the overall system architecture, broken down into its key subsystems (typically one or more diagrams), with associated description of these subsystems, their roles, data/information flow among them, main interfaces (internal and external) and protocols, as relevant.

A specific emphasis should be given to the elements which will be developed, customised, integrated in the framework of the project

This section shall also clearly point out the strategic role of the satellite component/s in the proposed system compared to potential alternatives.

The SSA shall provide a provisional list of the sites (or areas, if related to mobile units) where the system will be installed for the pilot utilisation.

The SSA shall clearly indicate the source of procurement for the different elements (e.g. purchase of commercial products (COTS), loan from partners or sponsors, developments performed within the contract) and the associated economic value, and whether they are long lead items.

3Design and Development Plan

Projects addressing development of hardware and/or software shall include a design and development plan to illustrate in a concise and conceptual manner the logical execution of the proposed development activities.

It shall define and include decision points upon which the course of the development will depend, together with the relevant quality standard and procedures, where applicable.

4Design Justification File

The SSA shall include the Design Justification File (DJF) documenting and detailing the trade-off processes performed to justify the design choices, and the associated design documents. This will apply to either the elements to be developed or the elements that need to be selected from already available solutions.

The following template provides the explanation of the different line items (which are generic to allow these forms to be used in different hardware and software areas):

Item/Area: Item or area

Date:Self explanatory

Design Choice: Statement of the issue that leads to design choices

Licensing: Compatibility of external components’ licenses with the licensing scheme of the product/ service

Solution:Proposed decision i.e. proposed best solution to the design decision

Alternatives: Alternative solutions considered and reasons for non-selection (these should be supported by analyses in the appendix)

Impact:Impact on other parts of the development

Comment: Other relevant information

Analyses:In appendix.

Note: the above line items should be modified to reflect the needs of your project, company procedures, etc.

Examples of the Justification Forms are given below.

Design Justification Form #1 - Item or area concerned

Item/Area
Date
Design Choice
Licensing
Solution
Alternatives
Impact
Comment
Analyses

Design Justification Form #2 - Item or area concerned

Item/Area
Date
Design Choice
Licensing
Solution
Alternatives
Impact
Comment
Analyses

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