> are microwave links still common? Yes, they have their purposes. I work in finance and we use microwave links to talk between systems in Chicago & New York.

> are microwave links still common? Yes, they have their purposes. I work in finance and we use microwave links to talk between systems in Chicago & New York. Fiber links are the backup, here! The reason is purely latency as the bandwidth of the fiber links is orders of magnitude higher. The major downside is the microwave links drop quite frequently as they're sensitive to the totality of the weather between data centers (e.g. any sort of precipitation as a crow flies between NYC & CHI and there's potential for dropped links).