The primary use of dextromethorphan is as a cough suppressant, for the temporary relief of cough caused by minor throat and bronchial irritation (such as commonly accompanies the flu and common cold), as well as those resulting from inhaled particle irritants.
As of Q4 2016, South Korea had the fastest average internet connection in the world at 26.1 Mbit/s according to the report State of the Internet published by Akamai Technologies. South Korea's speed is almost four times faster than the world average of 7.0 Mbit/s.
In terms of the fastest internet connection speeds, (that are not scientific tests and available for consumer or business use), South Korea is also a world leader. Other Asian countries also have some of the fastest internet in the world.