Verizon wants 25 ms switchover for large customers needing reliability.
Verizon is planning at least hundreds of thousands of 5G mmWave cells, many of which will be backhauled using NG-PON2 from Calix. (Below.) Recently, Brett Feldman of Goldman Sachs projected Verizon is spending $20B over the next several years; from different sources, I came to a similar conclusion last year.
"Verizon's announcement is legitimizing NG-PON2," Carl Russo of Calix asserts. "It's the right choice today for 5G and customers who need the failover reliability. Because you can switch wavelengths almost instantly and upgrade easily, it's very attractive for customers with growing demand."
He added, "The cost will come down with volume and time. Today, it's the right choice for many; going forward, we expect a very wide market."
NG-PON2 requires expensive lasers of a kind that haven't been mass produced. A half-dozen companies, Adtran as well as optics specialists, are working furiously to bring down the cost.