Version 1.0, August 31, 2001, Copyright, Hugh Jack 1993-2001

31.1 COMPUTER COMMUNICATIONS CATEGORIES

 

· Basic Categories

  1. · Interface to Sensors and Actuators
    1. - Uses readings from sensors to control devices in the environment
    2. - very simple protocols, but often requires specialized hardware and software.
  2. · Interface to computers
    1. - uses machine to machine connection for direct communication
    2. - can appear to be like a local area network
    3. - low speeds (eg. 300 baud, 1.2, 2.4 9.2 Kbaud)
  3. · Local Area Computer Networks
    1. - measured in distances from meters to kilometers
    2. - speed measured in Megabits/sec
    3. - medium includes, wire, fibre-optics, radio frequency
    4. - commonly available in all forms
    5. - inexpensive
  4. · Wide Area Computer Networks
    1. - from city wide, to global
    2. - speed measured in Kilobytes/second
    3. - medium includes, wire, fibre optics, satellite, microwave
    4. - access is costly (some mix of initial and variable costs), and geared to large corporations, or special applications.

 

· Classification of Interconnected processors (by Physical Size)

  1.  

Inter-processor Distance

Processors Located in Same

Example

0.1 m

Circuit Board

Data flow machine

1 m

System

Multi-

processor

10 m

Room

Local

network

100 m

Building

1 km

Campus

10 km

City

Long haul network

100 km

Country

1000 km

Continent

Inter-

connection of long haul networks

10000 km

Planet