問題文
The same guidance lists two more levers against toll fraud on a call control cluster. One of them is about an ad hoc conference and the other is about what to do where automatic registration has been left switched on. What does it recommend for each of the two?
選択肢
- Setting the conference to be dropped once no on-net party is left in it, and turning automatic registration off outright for any device that has not been entered by hand beforehand.
- Setting the conference to be dropped as soon as the party that raised it hangs up, and turning automatic registration off outright for any device that has not been entered by hand beforehand.
- Setting the conference to be dropped once no on-net party is left in it, and building a device pool whose search space is a restricted one for any device that registers by itself.
- Setting the conference to be dropped as soon as the party that raised it hangs up, and building a device pool whose search space is a restricted one for any device that registers by itself.