Transmission system vs Switching system-Difference between Transmission system and Switching system
This page compares Transmission system vs Switching system and mentions difference between Transmission system and Switching system.
Signal information (voice,data,image,video) which is generated at source need to be transported to the destination for various applications. For this reasons we need transmission and switching systems.
Entire communication system can be categorized into four major parts viz. end systems at customer premises, transmission system, switching system and signaling. The customer premise equipments include PC, Laptop, Tablet, Mobile or telephone, Fax, Telex etc. The signaling takes care of establishing connection between two end systems located at customer sides. Signaling include exchange of signals between all the system entities which covers end systems, switching exchanges, transmission elements etc. Let us understand transmission system and switching system. The figure-1 depicts simple block diagram of communication system.
The transmission link carry both information (e.g. voice, data) and signaling parts.
The common example of transmission links are as follows.
• Two wire transmission line
• Coaxial cable
• Microwave terrestrial link
• Fiber optic cable
• Satellite based communication link
• Infrared communication
The medium of transmission can be guided or unguided. The guided include copper, fiber etc. while unguided include microwave, satellite etc. The transmission system is characterised by three parameters viz. bandwidth of information to be carried, propagation delay and path attenuation from source to the destination.
Following modules are typically incorporated in transmitter and
receiver parts of the communication system.
• Analog to digital conversion at transmitter and D to A at receiver.
• Encoding (at transmitter) and decoding (at receiver).
• Modulation (at transmitter) and demodulation (at receiver)
• Multiplexing (at transmitter) and demultiplexing (at receiver)
• Multiple access techniques such as FDMA, TDMA and CDMA in order to have efficient usage of common resources of the communication system.
The system which provides switching of baseband information such as voice and data at intermediate points during transmission is known as switching system. Typically switching system is characterised by number of input and output lines.
Examples of switching systems include following modules or system.
• Telephone Exchanges
• Voice Switches
• Packet or data switches
• Routers or Gateways