This is technological babble even I can understand.
Ordinarily, Battlefield 4 communicates with the server 30 times a second, or at a frequency of 30Hz. However, with the latest CTE update, DICE has increased the data rate to 60Hz, meaning that player date is now sent to the server 60 times each second.
The difference this is making to the game experience is astounding. it is, in fact, night and day. As you might expect, doubling the communication of the client with the server greatly improves game experience, minimizing input lag, network lag, leading to overall improved responsiveness, and just an all around better online experience than it was before.
The new CTE update also improves the stability of the netcode otherwise.
All in all, this should be a beneficial update for Battlefield 4- some of the issues that have plagued it since launch, such as hit detection errors, and players glitching across the map, should now be a thing of the past.