Spectrum sharing keeps growing, as a trend in the Internet access business. TV white spaces is based on dynamic sharing. U.S. regulators are working to enable sharing of licensed government spectrum by commercial entities, with an early focus on mobile applications.

Pre-5G and full 5G protocols also incorporate methods for spectrum sharing, especially across mobile and Wi-Fi networks.

There are important developments in the 4G spectrum sharing area as well, both to allow Long Term Evolution sharing and sharing of Wi-Fi and LTE.

As you might expect, the amount of jockeying for position is intense. At least three different protocols for supporting LTE sharing with Wi-Fi are pushed.

LTE-U is supported by the 3rd Generation Partnership Project (3GPP).

License-Assisted Access (LAA) is a version of LTE-U specified in release 13 that includes Listen Before Talk (LBT) protocols to ensure WiFi and LTE can coexist. It is mandated in the Europe and Japan, but not the United States and some other markets.

MuLTEfire is a protocol developed by Qualcomm that doesn’t require a licensed anchor channel, so that venues or cable companies without licensed spectrum, also can deploy LTE-U.

As with earlier key protocol decisions, much hinges on the outcome. Sharing is going to happen. The fortunes of various service provider contestants, app providers and infrastructure suppliers will hang on the outcome.