How it works

On idle when there is no alert

When there is no active alert, the

NDS

regularly requests from the CUCM the list of all active phones in the enterprise and their IPs. The

NDS

will then cache this information so that it can be used in real time when an alert becomes active, without having to rely on the CUCM at that point.

During an alert

The following process is carried out when an alert is generated:

BlackBerry AtHoc

pushes the list of end users to activate along with their DNs to the

NDS

The

NDS

finds the IP of the phone for every DN and sends the IP phones a command to activate.

The IP phone uses the authentication enterprise parameter of the CUCM to authenticate the request.

Seeing that the Authenticator is the

NDS

, the IP phone requests (unless it already has it) the SSL certificate of the

NDS

from the CUCM server to ensure that it is calling the correct server.

After the IP phone gets the SSL Certificate of the

NDS

, it invokes the authentication function on the

NDS

After authentication is complete, the command is executed by the phone. If the command requires the display of text on the screen, the IP phone will go back to

NDS

to retrieve that text.

If audio is requested to be sent, the

NDS

also immediately starts streaming the audio on multi-cast for the IP phones to play.

Section:

Appendix A: Cisco IP Phone specifics