Subscriber Loop Design

The cables that connect the telephone handsets or other devices to the local switching office or end office is referred as subscriber loop or local loop. Every suscriber has his own pair of wires to the local switching office. Twisted pair local loop is an excellent transmission medium for analog voice signals. But it is limited to low frequency audio signals. The introduction of fiber cable needs a device at subscriber premises to convert electrical energy into light energy and this is the...

The Strowger Step By Step Switching System

Several electromechanical switching system were developed around 1880-1890 to eliminate the limitations of manual exchanges and to establish automatic exchanges to improve the speed and carry more leads subscribers . Among those electromechanical automatic switches, strowger's step by step switching system was the most pupular and widely used and even now in some part of the world, it is in use. The history of this switching system is described briefly in the following paragraph. The first...

Dms Switch Architecture

Coordinator Processor Ewsd

Hardware architecture of DMS-100. Fig. 6.11. Hardware architecture of DMS-100. Processor Modules. The main components of processor modules are DMS-Core Processor, file processor, Application Processor and LPP. The DMS-core processor supports the call processing, performs control function, down loading DMS super-node software and supports other peripheral controllers. The core processors is a set of central processing units. The file processor provides access to large data files for...

Digital Switching Systems

Various facilities of digital switching and transmission is the reason why the analog switching is slowly getting replaced by digital switching. The incorporation of digital switching and transmission technique into telecommunications altered the whole telecommunication industries setup. The reliability of digital switching system is becoming increasingly important for users of telephone services. Voice and or data can be represented using digital signals efficiently than analog signals. A...