Call waiting is a feature that is enabled by default on all dual-line ephone-dns.
There are some instances where you may wish to disable Call-Waiting but keep other benifits of a dual-line ephone-dn such as consultative transfer and conferencing.
To disable a directory number from accepting call-waiting requests use the command no call-waiting beepaccept at the ephone-dn.
To make it so a specific phone cannot generate call-waiting beeps to other phones use the command no call-waiting beepgenerate at the ephone-dn.
Lastly, Have you ever heard a call waiting beep on your phone, but not been able to get the other person to stop talking long enough for you to tell them you have another call? Try call-waiting ring at the ephone-dn. This will make your phone ring rather than beep when you get a call waiting beep.