Once a client is presented with the HSTS policy, it caches the information for the specified max-age period. During that period, the browser refuses to access the web service over unencrypted HTTP, and refuses to grant exceptions to certificate errors (if the site previously presented a valid, trusted certificate).
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The term laser originated as an acronym for light amplification by stimulated emission of radiation.
Using a lens, the light pulses are funneled into the fiber-optic medium where they travel down the cable. The light (near infrared) is most often 850nm for shorter distances and 1,300nm for longer distances on Multi-mode fiber and 1300nm for single-mode fiber and 1,500nm is used for for longer distances.