You are designing a link layer protocol for a link with bandwidth of $1$ Gbps ($10^9$ bits/second) over a fiber link with length of $800$ km. Assume the speed of light in this medium is $200000$ km/second. What is the propagation delay in this link?
Propagation delay : Time taken by the first bit to travel from sender to receiver end of the link.
Propagation delay = distance/transmission speed = d/s
Propagation delay = 800km/200000km/sec
Propagation delay = distance/speed of the medium = d/s