H LISTIC

Systems Engineering Matters

Presentation Overview

! The Case for Systems Engineering! Some Key Best Practices! Holistic Systems Engineering

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The Case For Systems Engineering

Section Overview

! The Case for Systems Engineering" What is Systems Engineering?" Characteristics of Effective SE" Why Worry?" Top 5 Signs you need improved SE" Benefits of Strengthened SE

! Some Key Best Practices! Holistic Systems Engineering+

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What is Systems Engineering?The Book Answer

! Definitions:-" An interdisciplinary approach that encompasses the entire technical effort, and evolves into and

verifies an integrated and life cycle balanced set of system people, products, and process solutionsthat satisfy customer needs. (EIA Standard IS-632, Systems Engineering, December 1994.)

" An interdisciplinary, collaborative approach that derives, evolves, and verifies a life-cycle balanced system solution which satisfies customer expectations and meets public acceptability.(IEEE P1220, Standard for Application and Management of the Systems EngineeringProcess, [Final Draft], 26 September 1994.)

" A logical sequence of activities and decisions that transforms an operational need into a description of system performance parameters and a preferred system configuration. (MIL-STD-499A, Engineering Management, 1 May 1974.)

! Key Phrases:-" Interdisciplinary, Collaborative, Customer Needs, System

Solution, Life-Cycle

SE principles have been largely developed by Aerospace and Military for large, complex projects.

Telecom industry has traditionally avoided such heavy overheads -but let’s take a look and see what’s useful…

Stakeholders

Customer StandardsBodies

Test &Verification

ProjectManagement

DesignDisciplines

What is Systems Engineering?The Holistic Answer

Working with all these…

…to enable:

- a winning product

- at the right time

Characteristics of Effective SE

! Customer-Oriented" Understands, captures and maintains customer requirements" Identifies key effectiveness measures for project success

! Whole System Solution" Develops and documents system solution which meets

customer expectations while optimising effectiveness

! Interdisciplinary" Involves all design & test disciplines participating in the

project

! Methodical" Adopts a deterministic and methodical approach to moving

from requirements, through design, to verification

! Whole Life-Cycle" Considers the requirements of all users – not only primary

operational users, but also manufacturing, maintenance and service “users”

Why Worry?! System complexity increases continually

" Modern telecommunication devices are converging –placing more and more demands on the overall system functionality

! Time-To-Market pressure unrelenting" Customers and investors continue to press for ever shorter

lead times (witness 3G development)

! Increasing use of outsourced R&D resources" These and other pressures force suppliers to make

increasing use of third party development resources

! Expensive R&D must outperform alternatives" With increasing use of Asian and East European design

centres, the focus for experienced western teams must be the challenge of rapid complex systems development using dispersed design teams

Systems Engineering capability will be THE key differentiator

Top 5 Signs you need improved SE

! High levels of change during detailed design" Senior technical staff bogged down with change requests

having “system impact”

! System Integration derails the plan" System development slows or stalls in integration. " Defects require reconsideration of the system design.

! Complex features jettisoned or never used" Complex system features are thrown away during

development due to difficulty of debug / verification" Customer never uses features designed in at significant cost

! Product is difficult to install and maintain" Customers find problems with setup and configuration" Troubleshooting and fault rectification is not well supported

! System underperforms against customer expectations

" System passes verification tests but fails to meet customer performance expectations

Benefits of Strengthened SE

! Provides methodical framework for system thinking" Replaces ad-hoc, unstructured text with integrated approach

to system definition" Uses standardised modelling techniques to ease

communications and leverage available tools

! Drives out system flaws early – before integration" Reduces high level design errors through early modelling

! Improves system effectiveness" Defines key system effectiveness parameters early in the

project to guide design – focuses design teams on what is important to the customer

! Greater ROI from development resources" Good SE practice means clarity for the whole development

team, and a reduction in holdups late in the program

Bottom line objective – better products, faster

Some Key Best Practices

Section Overview

! The Case for Systems Engineering! Some Key Best Practices

" Best Practices are not “One-Size-Fits-All”" Technical SE Process" Manage Requirements" Select a Formal Method" Use Executable Models" Validate Whenever Possible" Consider Process Economics

! Holistic Systems Engineering

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Best Practices are not “One-Size-Fits-All”! There follows a set of cornerstone principles

" They represent the key elements which underpin the Holistic SE approach

" They do not necessarily mean “heavyweight” process

! Different businesses and marketplaces require differing approaches to SE

" Degree of formality and traceability" How far iterative vs waterfall development can be used" How thorough system verification must be

Technical SE Process is Simple

! Same core procedure can be applied at every level of the design

! Using Effectiveness Measures makes trade-off decisions overt

Gather Requirements Analyse

RequiredBehaviour

Define Effectiveness

Measures

Perform Design Trade-Offs

Identify Possible Architectures

Iterate if no feasible design

Design Selected

Manage Requirements

! Catalogue and maintain customer requirements" Provides focus for all development effort" Vital to ensure the customer gets what he wants" Good tools exist

! Set a Product Vision! Consider all users, manufacturing, test and field

support personnel as well as the end customer or user

! Develop requirements model iteratively with the rest of the system

! Trace requirements through to Use Cases and design artefacts

" Supports verification and impact analysis

Select a Formal Method

! SE information must be accessible to many different disciplines

! Concise, unambiguous specification demands formality

! Consistent notation aids communication! Current trends favour the Unified Modelling

Language" Already dominant for Software Engineering" OMG has issued RFI on UML for Systems Engineering" Hardware modelling languages adopt object-oriented

techniques (eg SystemC)" Wide tool support is already available

Think Through Process! Notation and Methodology is not enough

" The process to be followed must be thought through for the project or enterprise

" Identify workflows, deliverables & CM strategy" Understand tool capabilities and limitations

! Iterative development" Design iterations to address key program risks early" Avoid Big Bang by seeking opportunities for early confidence-

building" Structured analysis allows partial release of early information

in a controlled way" Early release of key architectural scenarios allows detailed

design thinking to start earlier

! Use Case driven analysis" Structure the analysis of system functional requirements

through the construction of Use Case Models" Use Cases are the foundation of iteration planning

Use Executable Models

! Executable models can offer very early verification of system level designs

" Debugging paper specification is a slow and unreliable process

! A modelling framework which allows sections of the model to be independently refined can be very powerful for risk exploration

! Useful high level modelling can be often be achieved direct from simple UML models

! Modelling languages are emerging which support typical hardware and software semantics (eg SystemC)

Use Automated Tests

! Use Case methodology supports test specification at each level

! Investing in automated test environments pays off in later iterations and maintenance phase

" Rapid regression testing" Reduces design errors entering integration" Provides basis for confident evolution in the future

! Test assets must be treated as project deliverables" Just as important as the operational code

Validate Whenever Possible

Target Customer Specify Requirements

Design against Specification

Test against Specification

Target Customer Specify Requirements

Design against Specification

Test for Customer

Satisfaction

The Verification Loop

The Validation Loop

Consider Design Process Economics(Gospel according to Don Reinertsen1)

! Every project should know sensitivity of life-cycle profit to four key parameters

" Development Expense" Unit Cost" Performance Shortfall" Schedule Delay

! Knowing this information gives project management vital rules for day-to-day decisions

! The true cost of bottlenecks and queues in the development process can be evaluated

1Managing The Design Factory, Donald G Reinertsen, Free Press, 1997

Holistic Systems Engineering

Section Overview

! The Case for Systems Engineering! Some Key Best Practices! Holistic Systems Engineering

" Track Record" Recent Project" Business Model

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Track Record! 20 years of communications experience

" 12 years of commercial wireless systems development

! Broad range of systems" Switching systems with high-availability requirements" Semiconductors and ASICs" Terminals for Automotive applications" Externally-mounted FWA systems

! Standards body experience" ETSI BRAN and IEEE 802 attendee

! Broad range of technologies" 3GPP" WLAN" FWA" DECT" PMR

Recent Project Example

! Development of WLAN chipset for major European telecom supplier

" Provided senior systems engineering effort to client team" Proactively developed structured process as part of the

engineering activity

! Requirements Management using Requisite Pro" Structured requirements database extracted from project

input documents" Functional requirements traced to Use Cases within tool

environment

! Use of UML based tools to construct systems architecture model

" System Use Cases captured and analysed" Single model embraced software and hardware" Model formed architectural database – one fact in one place" UML model linked to executable model in SystemC" Formal (“paper”) specifications extracted from UML model

Business Model

! Holistic would be happy to support your projects in any of the following ways:" To augment your team with experienced telecom systems

engineering skills" To assist in developing and/or strengthening systems

engineering practice" To support the evaluation of tools or process

improvements" To support the development or delivery of training

material to establish a systems engineering practice! Contact Details

mailto: tmoore@holistic-systems.nu