IBM, accessibility guidelines, 186
icons, consistent meanings of, 182
identification details for users, 285
identifier. See also IDs
unique for each requirement, 13, F-33
identity card issuance, 201
ID requirement pattern, 97–101
IDs, allocation of, 99, 263
IEEE (Institute of Electrical and Electronics Engineers) technical standards, 74
IETF (Internet Engineering Task Force), 74
images, 123, 180–181, 188. See also graphics
implementation, 40, F-43
implicit interactions, 62
inaccessible data, filtering, 311
inaccessible functions, hiding or disabling, 306
inactive information, removal of, 217
inactivity time-out, 301
incorrect password entry, recording, 149
incremental approach to requirements, 3, 10, F-2, F-6, F-26, F-28
independent reviews, approach to, 8, F-19
indexes of data archives, 114
industry-specific codes of practice, 71
industry-specific patterns, 43
industry-specific regulations, 71
industry-specific standards, 75
inflexibility
system, 135, 138
temporal, 256
informal elements in a requirement definition, 13, F-42–F-43
informal part of a requirements specification, 6–7, F-11–F-12
information. See also data
backing up, 123
changes, 122
described, 85
devolution of, 135
domain, 29
entry, multi-part, 122, 124–125
flowing in an interaction, 64
form of, 86
gathering, F-17
gathering from people, 8
infrastructure, 154
inquiries for, 123
integrity, 122, 123
restricting access to, 305
retrieval mechanisms, 154
standards, 71
storage, 120, 124, 154
types of, 123
information requirement pattern, 85–117
infrastructures
defined, 17, F-63
disentangling from business functions, F-67
extendability requirements and, 250
fewer distinct actors, F-69
identifying, 30
improving the boundary of each, F-67
for information storage, 120, 154
for a new domain, 45
numbered list of, F-65
overviews, 30, 31
process for identifying and specifying, F-64–F-68
relationships with domains and requirement patterns, 30, 31
reporting, 155, 189–190
in a requirement pattern diagram, 33
requirements, 27, F-67, F-68
requiring technical analysis, F-67
treating a business rule product as, 38
user interface, 155, 187–189
using from other domains, 30
Infrastructures section in a requirements specification, 17, F-54, F-63–F-68
inheritance relationship between requirement patterns, 32, 33
initial customer capacity, 216
input, 171. See also throughput
input interpretation by multiness instances, 268
inquiry
automatic refreshing of, 157, 159, 177, 188
dynamic use, 214
for information, 123
for living entities, 131
multiness requirements and, 263
from offline storage, 117
versus report, 162
response time, 200
scalability requirements and, 245
static capacity, 217
inquiry requirement pattern, 156–161
inspection of a requirements specification, F-19
installability requirement pattern, 274–279
installation requirements for drivers, 251–252
installing
driver software, 251–252
scalability requirements and, 245
instances, giving users access to, 270
Institute of Electrical and Electronics Engineers (IEEE) technical standards, 74
integers, data type, 87
integrity, 122, 123, 126, 140
intent of a requirement, F-42
interactions
across an interface, 57, 62, 63
describing an activity across the interface, 52
with inquiries, 157
specifying types of, 63, 64
interactive documentation, 84
interactive tutorial, 83–84
interest calculations, 104–106
interfaces
defining, 15–16, 54, 55, F-55
describing within other systems, F-57
development considerations, 62
documentation of, 61
examples, 56, F-58
indeterminate number of, 53
influencing the design of, 63
of an infrastructure, 31
interactions in requirements, 63
to multiple systems for the same purpose, 52, 54
ownership of, 63
passport control for, 58
positioning in a context diagram, F-57
security requirements for, 60–61
specifying between systems, 52
standards defining, 79
switching to new versions of, 59
templates, 56, 64
testing, 62, 65
upgrading, 59–61
as weak links, 52
interface adapters, 53–54
Interface Developer's Guide, writing, 61
interface ID, 55, 64
interface name, 55, 64
interface ownership, 54–55
interface resilience requirements, 58
internal interactions, 52
internal users, 212, F-57
international dimension, unparochialness and, 258–260
International Organization for Standardization (ISO), 74
International Standard Book Number (ISBN), F-51
Internet Engineering Task Force (IETF), 74
Internet Explorer Web browser, 68
Internet-based retail system, F-35–F-36
inter-system interaction requirement pattern, 47, 62–65
inter-system interface requirement pattern, 51–62
inter-system interfaces, 15–16, 65, 206, F-55
interview approach to gathering information, F-17, F-18
introduction of the glossary, F-44
Introduction section of a requirements specification, 12–15, F-30, F-31–F-53
invalid interactions, testing for an interface, 65
invisible ID scheme, 101
invocation requirements
information infrastructure, 154
for an infrastructure, F-67, F-68
in an infrastructure overview, 31
reporting infrastructure, 189–190
user interface infrastructure, 187–188
"is-a-kind-of" relationship, 37
ISBN (International Standard Book Number), F-51
ISO (International Organization for Standardization), 74
ISO 639 standard for natural languages, 76, 272
ISO 3166 standard for countries and regions, 76
ISO 4217 standard for currencies, 76, 142
isolated changes, 123
iterative development, F-6