This read-only enumeration reports the call-signaling state of the IP side of a port's connection, idle, call initiated, alerting, connected, and so on, the IP-network counterpart to linePortState's telephone-line-side view. Admins compare this against linePortState on the same port to see whether a stuck call is stalled on the traditional telephony leg or the VoIP/IP leg of the connection. For example, if linePortState shows a call connected but ipPortState is stuck at overlapsend, the problem is isolated to the IP signaling side of that call.