Patent ID: 8438213

Claim:
A method for presenting telephone state information, comprising: monitoring, by a user telephone line monitoring device, the state of a user telephone line of a first user, generating telephone state information according to a current state of the user telephone line, and sending the generated telephone state information to a presence client end of the first user; receiving, by the presence client end of the first user, the telephone state information, and sending the received telephone state information to a presence server via an IP network; receiving, by the presence server, the telephone state information, and sending the received telephone state information to a presence contact end of a second user that has subscribed the telephone state information of the first user; and receiving, by the presence contact end, the telephone state information, and displaying presence information of the telephone state information; wherein the monitoring the state of the user telephone line comprises monitoring the electronic feature of the user telephone line, wherein the electronic feature of the user telephone line is one of, a direct current of 48V with a current less than 5 μA, indicating the user telephone is in an idle state, which is a state without an incoming call or an outgoing call and the telephone being hang on normally, a direct current of approximate 10 to 20V with a fluctuating current, indicating the user telephone is in a calling state, which is a state when the user initiates a call or receives a call, a polarity reversal signal, indicating the user telephone is in a connected state, which is a state when a call is connected and the called party picks up the phone, and an alternating current signal with tens of volts added to the user telephone line, indicating the user telephone is in a ringing state, which is a state when the user is called; and wherein the user telephone line monitoring device comprises two telephone interfaces, wherein one of the two telephone interfaces is connected to a telephone socket connecting with a switch, and the other of the two telephone interfaces is connected to the monitored telephone; the monitoring device is to obtain the current state of the user telephone line by monitoring the content of a register in the monitoring device, wherein the register is to monitor the working state; and wherein the content of the register in the monitoring device is to change when a user uses a telephone connected with the user telephone line; and the state signal processing device is to generate a user telephone line change notification according to the change of the register and send the user telephone line change notification via the monitoring interface to the presence client end.