Q. Explain about blocking probabilityand Grade of service? And what do you mean by delay systems in telecommunication networks?

Ans:

Grade of service: In loss systems, traffic carried by the network is normally lower than actual traffic offered to network by the subscribers. Overload traffic is rejected and thus it isn't carried by network. Amount of traffic rejected by network is an index of quality of the service offered by network and is called grade of service (GOS) and is stated as the ratio of lost traffic to offered traffic. Offered traffic is product of the average number of calls generated by users and average holding time per call. GOS is given by

GOS = A-A₀ / A₀

Where

A = offered traffic

A₀ = carried traffic

A-A₀ =  lost traffic