A method for acquiring an Internet Protocol - IP - address, the method comprising: receiving (S101, S201, S301), by a network side device, a request message of a first protocol sent by a terminal, the request message comprising an access request address; forwarding the request message of the first protocol to a server; receiving (S102, S202, S304), from the server, a web page comprising a scripting language code, the web page being based on the request message of the first protocol; returning (S102, S202), to the terminal, the web page; receiving (S103, S203), from the terminal, a request message for establishing a communication connection, sent by the terminal by running the scripting language code; establishing (S104, S203) the communication connection to the terminal based on the request message for establishing the communication connection; receiving, from the terminal, a data packet of a second protocol generated based on the scripting language code by using the communication connection; determining a source IP address for sending the data packet of the second protocol; adding the source IP address to a response packet of the second protocol, and returning the response packet of the second protocol to the terminal; receiving an IP address returned by the terminal based on the source IP address comprised in the response packet of the second protocol; and using the returned IP address as a first IP address of the terminal, wherein the first IP address of the terminal is an authentic IP address of the terminal; determining a second IP address of the terminal based on the request message of the first protocol; and performing risk control processing on the terminal based on the first IP address and the second IP address, wherein performing the risk control processing comprises: determining whether the first IP address and the second IP address are different; and if the first IP address and the second IP address are different, checking a historical activity record of the first IP address. receiving (S101, S201, S301), by a network side device, a request message of a first protocol sent by a terminal, the request message comprising an access request address; forwarding the request message of the first protocol to a server; receiving (S102, S202, S304), from the server, a web page comprising a scripting language code, the web page being based on the request message of the first protocol; returning (S102, S202), to the terminal, the web page; receiving (S103, S203), from the terminal, a request message for establishing a communication connection, sent by the terminal by running the scripting language code; establishing (S104, S203) the communication connection to the terminal based on the request message for establishing the communication connection; receiving, from the terminal, a data packet of a second protocol generated based on the scripting language code by using the communication connection; determining a source IP address for sending the data packet of the second protocol; adding the source IP address to a response packet of the second protocol, and returning the response packet of the second protocol to the terminal; receiving an IP address returned by the terminal based on the source IP address comprised in the response packet of the second protocol; and using the returned IP address as a first IP address of the terminal, wherein the first IP address of the terminal is an authentic IP address of the terminal; determining a second IP address of the terminal based on the request message of the first protocol; and performing risk control processing on the terminal based on the first IP address and the second IP address, wherein performing the risk control processing comprises: determining whether the first IP address and the second IP address are different; and if the first IP address and the second IP address are different, checking a historical activity record of the first IP address. determining whether the first IP address and the second IP address are different; and if the first IP address and the second IP address are different, checking a historical activity record of the first IP address.