Explain in short six characteritics of Transmission Media.
Characteristics of Transmission Media:
(i) Bandwidth is the measure of the capacity of a medium to transmit data.
(ii) Data transmission rates is number of bits transmitted per second.
(iii) Bandwidth of a cable depends on cable length.
(2) Band usage
(i) The bandwidth is shared so that maximum usage is obtained.
(ii) There are two transmission modes, base band and broad band transmissions.
(iii) Base band devotes the entire capacity of the medium to one communication channel.
(iv) Broad band enables two or more communication channels to share the bandwidth of
(v) The base band and broad band transmission modes are shown in following figure
(i) Attenuation is a measure of how much a signal weakens as it travels through a medium.
(ii) As signals pass through the medium, part of the signal is absorbed and makes the signal weak.
(4) Immunity from electromagnetic interference (EMI)
(i) Electromagnetic interference consist of outside electromagnetic noise that distorts the signal in a medium.
(ii) EMI is interfering the signals and makes difficult for computers to decode the signal.
(5) Cost of media
(i) One major factor in purchase decision of any networking component is its cost.
(ii) For a new fast technology, cost is also more expensive.
(iii) Decision depends upon application and standard of the resources.
(iv) Therefore, the network designer must settle for something, which is cheaper and robust.
(6) Installation requirement
(i) Some transmission media requires skilled labour to install. This increases cost of network and it may cause certain delay.
(ii) Before installation we need to prepare actual physical layout of network.