Mobile Applications - Guide to Cloud Computing for Business and Technology Managers - page 469

architecture and structure consisting of reusable components reconfigurable
in a scalable framework can be an effective base model for creating variable
(or built-for-change) systems. For achieving this, the nature of the framework
appears to be a critical factor. We can introduce the framework/component
concept, by looking at three types of construction toys and observing how
they are used in practice, namely, Erector Set kit, LEGO kit, and Model
Builder's kit.
You can build virtually anything over and over again with either of these
toys; but fundamental differences in their architectures give each system
unique dynamic characteristics. All consist of a basic set of core construction
components and also have an architectural and structural framework that
enables connecting the components into an unbounded variety of configura-
tions. Nevertheless, the Model Builder is not as reusable in practice as Erector
Set; and, the Erector Set is not as reusable or reconfigurable or scalable in
practice as LEGO, but LEGO is more reusable, reconfigurable, and scalable
than either of them. LEGO is the dominant construction toy of choice among
preteen builders—who appear to value experimentation and innovation.
The Model Builder's kit can be used to construct one object like airplane
of one intended size. A highly integrated system, this construction kit offers
maximum esthetic appeal for one-time construction use; but the parts are
not reusable, the construction cannot be reconfigured, and one intended size
precludes any scalability. But it will remain what it is for all time—there is
zero variability here.
Erector Set kits can be purchased for constructing specific models, such
as a small airplane that can be assembled in many different configurations.
With the Erector Set kit, the first built model is likely to remain as origi-
nally configured in any particular play session. Erector Set, for all its modu-
lar structure, is just not as reconfigurable in practice as LEGO. The Erector
Set connectivity framework employs a special-purpose intermediate subsys-
tem used solely to attach one part to another—a nut-and-bolt pair and a 90°
elbow. The components in the system all have holes through which the bolts
may pass to connect one component with another. When a nut is lost, a bolt
is useless, and vice versa; when all the nuts and bolts remaining in a set
have been used, any remaining construction components are useless, and
vice versa. All the parts in a LEGO set can always be used and reused, but
the Erector Set, for all its modularity, is not as reusable in practice as LEGO.
LEGO offers similar kits, and both toys include a few necessary special
parts, like wheels and cowlings, to augment the core construction compo-
nents. Watch a child work with either and you will see the LEGO construc-
tion undergoes constant metamorphosis; the child may start with one of the
pictured configurations, but then reconfigures the pieces into all manner
of other imagined styles. LEGO components are plug compatible with each
other, containing the connectivity framework as an integral feature of the
component. A standard grid of bumps and cavities on component surfaces
allow them to snap together into a larger configuration—without limit.