Network performance indicators are indicators to measure network performance, including bandwidth, delay, and bandwidth delay product.
performance index
There are three main network performance indicators:
1. Bandwidth
The common bandwidth unit is
Kilo bits per second, i.e. kb/s (103 b/s)
Mega ratio per second, i.e. Mb/s (106 b/s)
Gigaby per second, i.e. Gb/s (109 b/s)
Terabitation per second, i.e. Tb/s (1012 b/s)
Note: In the computer world, K = 2 = 1024, M = 2, G = 2, T = 2.
2. Delay
The time required for a message or packet to be transmitted from one end of a network (or a link) to the other
Total delay= transmission delay +Propagation delay+processing delay+queuing delay Bandwidth times Propagation delay , that is, the largest on the chain Bits 。 
