# Line and protocol status events

Event | Informational/ Transitional | Solicited/ Unsolicited | Indicates that...
--- | --- | --- | ---
NCCEVN_LINE_IN_SERVICE | Transitional | Unsolicited | The network placed the line in service (was out of service).
NCCEVN_LINE_OUT_OF_SERVICE | Transitional | Unsolicited | The network placed the line out of service (was in service).
NCCEVN_PROTOCOL_ERROR | Informational | Solicited/ Unsolicited | A two channel call transfer failed or an error condition occurred. The call may be in an unusable state.
NCCEVN_PROTOCOL_EVENT | Informational | Solicited/ Unsolicited | A protocol-specific event occurred.