A Rationale-based Model for Architecture Design Reasoning

More documents

Recommendations

Info

Chapter 6 Representing architecture design rationale In the previous chapter, we have obtained the findings from a survey to support the capture and use of architecture design rationale. Similar arguments have been suggested by many others for different reasons. First, the design of a large system involves collaboration of designers who specialise in different aspects of the system. Design rationale can serve as a tool to clarify issues and assumptions that are tacit and implicit [88, 135]. Second, design rationale help to deliberate and justify system designs, such designs should be carefully considered, objective and unbiased [103]. Third, the tacit design knowledge of a system may be eroded when it is not captured [119]. Designers who understand the design may not be available for consultation. This can be very costly to system maintenance. Retaining tacit design knowledge could save time, reduce long-term cost, and help deliver software of better quality because designers would not have to second-guess the rationale behind the design [33]. Architecture design rationale is not very useful by itself. It is more useful when it relates requirements to design objects. This relationship is the basis to model architecture design rationale. Architecture Rationale and Elements Linkage (AREL) is created for this purpose. In Section 6.1, we look at the meaning of a design reason, which may have many interpretations. We discuss two types of design reasoning and their relevance in design decisions. We describe the concept of architecture design decision and its relationships with architecture elements in a conceptual model. We then develop the AREL representation for modelling architecture design rationale (in Section 6.2). 1 1 This chapter is based on our work published in [161]. 81
6.1. A conceptual model for design reasoning AREL comprises two fundamental elements, Architecture Rationale (AR) and Architecture Elements (AE). AR represents the design justification at a decision point. AE represents the design artefact which participates in a decision as an input or an outcome. They are described in details in Sections 6.4 and 6.3, respectively. 6.1 A conceptual model for design reasoning When architects and designers make design decisions, what do they consider as a reason or an intention? Should a requirement or a constraint be considered a reason for a design? Or is it some generic justification that allows designers to judge that a design is better than its alternatives? Design is a process of synthesising through alternative solutions in the design space [141]. Reasoning to support or reject a design solution is one of the fundamental steps in this process. The concept of a reason has many dimensions. We argue that design reasoning come in two forms: motivational reasons and design rationale. Motivational reasons are the reasons which motivate the act of making a design and providing a context to the design. They are goals to be achieved by the architecture design, or they are factors that constrain the architecture design. An example is a requirement. Although a requirement by itself is not a reason, but the need of requirement is the reason for the design. There are a few aspects to a motivational reason: • Causality - a motivational reason is an impetus to a design issue. As such, it is a cause of a design decision. • Goal - a motivational reason can be a goal or a sub-goal to be achieved. • Influence - a motivational reason can influence a decision by ways of supporting, rejecting or constraining a decision. • Factuality - a motivational reason can represent information that is either a fact or an assumption. A motivational reason can be a requirement, a goal, an assumption, a constraint or a design object exerting some influence on the architecture. It is important to represent motivational reasons explicitly as inputs to the decisions so that they are given proper attention in the decision making process. As suggested by [135], in order to have a deep understanding of software systems, undocumented assumptions have to be re-discovered. 82
Page 1 and 2:
A Rationale-based Model for Archite
Page 3 and 4:
maintenance. These techniques can h
Page 5 and 6:
Declaration This thesis contains no
Page 7 and 8:
2.2.6 DoD Architecture Framework .
Page 9 and 10:
5.4.6 Risk assessment in architectu
Page 11 and 12:
8.2 The architecture rationalisatio
Page 13 and 14:
12.2 Contributions . . . . . . . .
Page 15 and 16:
6.10 ≪AR≫ and ≪AAR≫ Stereot
Page 17 and 18:
11.13A Process to Synchronise Chang
Page 19 and 20:
5.13 Design Rationale Helps Evaluat
Page 21 and 22:
that architecture design is highly
Page 23 and 24:
1.2. Research motivations and resea
Page 25 and 26:
1.2. Research motivations and resea
Page 27 and 28:
1.4. Structure of the thesis the ch
Page 29 and 30:
Part I Problem Analysis 10
Page 31 and 32:
2.1. Industry practice of design ra
Page 33 and 34:
2.2. Architecture frameworks and de
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Chapter 3 Related work in design ra
Page 45 and 46:
3.2. Why do we need design rational
Page 47 and 48:
3.2. Why do we need design rational
Page 49 and 50: 3.3. Existing methods for capturing
Page 57 and 58: 3.4. Other related studies 3.3.7 Qu
Page 59 and 60: 3.4. Other related studies evolutio
Page 61 and 62: 3.5. How well design rationale meth
Page 63 and 64: 3.5. How well design rationale meth
Page 65 and 66: Chapter 4 Research methodology and
Page 67 and 68: 4.1. Software engineering research
Page 69 and 70: 4.2. The chosen research and valida
Page 71 and 72: Part II Architecture Design Rationa
Page 73 and 74: on a regular basis. Their inputs ha
Page 75 and 76: 5.1. Architecture rationale in the
Page 77 and 78: 5.2. Survey methodology data collec
Page 79 and 80: 5.3. Survey findings experience). I
Page 81 and 82: 5.3. Survey findings Table 5.1: Fre
Page 83 and 84: 5.3. Survey findings Business Goals
Page 85 and 86: 5.3. Survey findings 5.3.5 Document
Page 87 and 88: 5.3. Survey findings Table 5.8 summ
Page 89 and 90: 5.3. Survey findings We used Spearm
Page 91 and 92: 5.3. Survey findings previous desig
Page 93 and 94: 5.4. Discussion of findings Since t
Page 95 and 96: 5.4. Discussion of findings or cons
Page 97 and 98: 5.5. Limitations and use design rat
Page 99: Part III The Representation and App
Page 103 and 104: 6.2. Architecture Rationale and Ele
Page 105 and 106: 6.2. Architecture Rationale and Ele
Page 107 and 108: 6.3. Architecture elements Figure 6
Page 109 and 110: 6.4. Architecture rationale Figure
Page 111 and 112: 6.4. Architecture rationale • ris
Page 113 and 114: 6.4. Architecture rationale depicts
Page 115 and 116: 6.5. The extended AREL To prevent c
Page 117 and 118: 6.6. A UML representation of AREL a
Page 119 and 120: 6.6. A UML representation of AREL a
Page 121 and 122: 6.7. AREL usability AE by ≪AEsupe
Page 123 and 124: 6.8. Summary The AREL model is exte
Page 125 and 126: 7.1. The EFT system reasoning, a co
Page 127 and 128: 7.1. The EFT system The processing
Page 129 and 130: 7.1. The EFT system not chosen beca
Page 131 and 132: 7.1. The EFT system Figure 7.5: Int
Page 133 and 134: 7.1. The EFT system sequence checki
Page 135 and 136: 7.1. The EFT system Figure 7.7: Dec
Page 137 and 138: 7.1. The EFT system Therefore, in a
Page 139 and 140: 7.1. The EFT system Figure 7.10: De
Page 141 and 142: 7.2. An empirical study to validate
Page 151 and 152:
7.3. Summary The case study is spec
Page 153 and 154:
8.1. Background Based on these assu
Page 155 and 156:
8.2. The architecture rationalisati
Page 157 and 158:
Page 159 and 160:
Page 161 and 162:
Page 163 and 164:
8.3. Other applications of ARM As d
Page 165 and 166:
8.3. Other applications of ARM Figu
Page 167 and 168:
8.3. Other applications of ARM area
Page 169 and 170:
Chapter 9 Architecture rationale an
Page 171 and 172:
9.1. Background 9.1 Background In t
Page 173 and 174:
9.2. Traceability of architecture r
Page 175 and 176:
9.4. AREL and eAREL traceability ap
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Chapter 10 Architecture decision de
Page 187 and 188:
10.1. Background 10.1.2 Introductio
Page 189 and 190:
10.2. Building a BBN to represent a
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Page 197 and 198:
10.3. Reasoning about change impact
Page 199 and 200:
Page 201 and 202:
Page 203 and 204:
Page 205 and 206:
Page 207 and 208:
Page 209 and 210:
10.5. Summary design object may cau
Page 211 and 212:
11.1. Capturing architecture design
Page 213 and 214:
11.1. Capturing architecture design
Page 215 and 216:
11.2. Checking AREL models Figure 1
Page 217 and 218:
11.3. Tracing AREL models Figure 11
Page 219 and 220:
11.4. Analysing AREL with BBN • S
Page 221 and 222:
11.5. Limitations Figure 11.13: A P
Page 223 and 224:
Chapter 12 Conclusions 12.1 Summary
Page 225 and 226:
12.2. Contributions reasoning metho
Page 227 and 228:
12.2. Contributions implementations
Page 229 and 230:
12.3. Future work architecture deci
Page 231 and 232:
12.3. Future work to examine the co
Page 233 and 234:
BIBLIOGRAPHY [10] B. W. Boehm, Soft
Page 235 and 236:
BIBLIOGRAPHY [37] A. Eden and R. Ka
Page 237 and 238:
BIBLIOGRAPHY [62] J. D. Herbsleb an
Page 239 and 240:
BIBLIOGRAPHY [89] N. Lassing, D. Ri
Page 241 and 242:
BIBLIOGRAPHY [115] D. L. Parnas,
Page 243 and 244:
BIBLIOGRAPHY [142] Z. Simsek and J.
Page 245 and 246:
BIBLIOGRAPHY [167] W. F. Tichy, N.
Page 247 and 248:
Appendix A AREL Tool User Manual 1
Page 249 and 250:
4.1 AREL Check Model When the Check
Page 251 and 252:
4.2 AREL Model Tracing AREL model t
Page 253 and 254:
Figure 9 - result of downward trace
Page 255 and 256:
To initiate the graph’s creation,
Page 257 and 258:
onto the diagram 14 Assign values t
Page 259 and 260:
Useful Definitions The following ar
Page 261 and 262:
) Some projects only c) Not at all
Page 263 and 264:
19. I revisit architecture design d
Page 265 and 266:
Complaint Procedure If you have any
Page 267 and 268:
Privacy Protection Only investigato
Page 269 and 270:
B. Exploring design reasoning. 1. W
Page 271 and 272:
3. Why does the system use asynchro
Page 273 and 274:
C. General Comments on AREL Modelli
Page 275:
IEEE Computer Society Press. A. Tan
show all

A Rationale-based Model for Architecture Design Reasoning

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?