Concepts of Regulatory, Modularity and Locality

Concepts of Regulatory, Modularity and Locality:

 The hierarchical design approach reduce the complexity by dividing the Large system into several sub-modules.

 Other design concept and design approach are also need to simplify the process.

Regularity -- means that the hierarchical decomposition of large system should result it not only simple, but also similar blocks, as much as possible.

•  A good example of regularity in the design of array structures consisting of identical cells.
•  Regularity can exist at all level of abstraction at the transistor level, uniformly sized transistors simplify the design and at the logic level, identical gate structures can be used.
•  If the designer has small library of well characterized basic building blocks, a number of different functions can be constructed by using this principle.
• Regularity usually  reduce the number of different models that need to be designed and verified, at all  level of abstraction.

Modularity - Modularity in design means that the various functional blocks which make up the larger system must have well-defined functions and interfaces. 

• Modularity allows that each block or module can be designed relatively independently from each other, since there is no ambiguity  about the function and the signal interface of the blocks.
• All of the blocks  can be combined with ease at the end of the design process, to form a large system.
• The concept of modularity enables the parallelization of the design process .The well-defined functionality and signal interface also allow the use of generic modules in various designs.

Locality- By defining well-characterized interfaces for each module in the system, we effectively ensure that the internals of each module become unimportant to the exterior modules.

•  Internal details remains at the local level.
• The concept of locality also ensures that connections are mostly between neighboring modules, avoiding long-distance connections as much as possible.This last point is extremely important for avoiding long interconnect delays.