Many devices cannot continuously listen for connections from a management server. Other devices simply do not wish to “open a port” (i.e. accept connections) for security reasons. However, most devices can receive unsolicited messages, sometimes called “notifications”. Some handsets, for example, can receive SMS messages. Other devices may have the ability to receive other, similar datagram messages.
A management server can use this notification capability to cause the client to initiate a connection back to the management server. This connection might be over HTTP, WAP or another transport protocol.
The contents of such a “Notification Initiation Alert” might be empty, but the message itself may be signed such that the client can authenticate it. The result of receiving such an alert would be for the client to initiate a connection to the management server that sent the alert. In this scenario, the client might verify that this management server is among those authorized to request such activity. Alternatively, the contents of the alert might indicate that another management server should be contacted.
An identical effect of receiving a Notification Initiation Alert can also be caused in other ways. For example, the user interface (UI) of the device may allow the user to tell the client to initiate a management session. Or, the management client might initiate a session as the result of a timer expiring. Of course, a fault of some type in the device could also cause the management client to initiate a session.
