Another element of in-band signaling addressed by SS7 is network efficiency. With in band signaling, the voice channel is used during call setup which makes it unavailable for actual traffic. For long distance calls, the talk path may traverse several nodes which reduces usable node capacity. With SS7, the connection is not established between the end points until all nodes on the path confirm availability. If the far end is busy, the caller gets a busy signal without using any network resources.