Notification Broker: Does not create notification messages, but manages the notification process on behalf of one or more publishers.

通知代理：不会创建通知消息，但代表一个或多个发布者管理通知流程。

youdao

Instead, a push notification is sent to all users in attendance, giving them a choice to create a group album of shared photos.

ENGADGET

Apple will create a website for people interested in cashing in on the settlement and send an e-mail notification to roughly 23 million customers.

CNN: Apple settles suit over in-game iTunes purchases by kids