Measuring capacity of communication media

In data communication, the transmission medium is also known as channel . The capacity of a channel is the maximum amount of signals or traffic that a channel can carry . It is measured in terms of bandwidth and data transfer rate.

Bandwidth

• Bandwidth of a channel is the range of frequencies available for transmission of data through that channel. 
• Higher the bandwidth, higher the data transfer rate. 
• Normally, bandwidth is the difference of maximum and minimum frequency contained in the composite signals. 
• Bandwidth is measured in Hertz (Hz). 

1 KHz =1000 Hz 

1 MHz =1000 KHz = 1000000 Hz

Data transfer rate

• Data transfer rate is the number of bits transmitted between source and destination in one second. 
• It is also known as bit rate. 
• It is measured in terms of bits per second (bps). 
• The higher units for data transfer rates are: 
• 1 Kbps=210 bps=1024 bps 
• 1 Mbps=220 bps=1024 Kbps 
• 1 Gbps=230 bps=1024 Mbps 
• 1 Tbps=240 bps=1024 Gbps