問題文
An incoming INVITE advertises both named events inside the media stream and the method that subscribes and then notifies. How does a border element handle the two of them for receiving digits?
選択肢
- The named events inside the media stream, until a subscription is actually raised, since reading both of the paths at once would report every digit twice over.
- The method that subscribes and notifies, until the media stream falters, since a digit under a subscription is the more dependable of the two paths by far.
- Neither of the two paths until one of them is withdrawn, since a pair advertised together leaves the choice of a single path unsettled between the ends.
- Both of the two paths at the very same time, since a digit that lands on either of them has to be handed on to the leg that leaves the border element.