Method for determining whether an IP address is attributed to a terminal in a communication network

A method for determining whether an IP address is attributed in a communication network comprising at least one gateway, said method being implemented by the gateway and comprising:

• receiving, by the gateway, a plurality of messages exchanged by means of an IP protocol in the communication network;
• generating, by the gateway, a filter for extracting first address test messages of the plurality of messages, each first address test message targeting a target IP address and requesting any terminal to which the target IP address is attributed to send an address-signalling message in response to receiving said first address test message;
• receiving, by the gateway, a first address test message targeting a target IP address;
• in response to receiving the first address test message:
• recording, by the gateway, said target IP address in a table managed by the gateway;
• initializing, by the gateway, a timer of a predefined time interval k;
• sending, by the gateway, in the communication network of the gateway, a predetermined number of second address test messages targeting a terminal having attributed said target IP address, wherein a subsequent sending of a second address test message targeting said target IP address is separated in time from a previous sending of a second address test message targeting said target IP address by the predefined time interval k;
• for each sending of a second address test message targeting said target IP address:
• awaiting, by the gateway for the predefined time interval k, reception of an address-signalling message responding to the second address test message from a terminal having attributed said target IP address;
• determining, by the gateway, that the target IP address is attributed to a terminal in response to receiving an address-signalling message having said target IP address as its source IP address;
• in response to determining that the target IP address is attributed to the terminal:
• obtaining, by the gateway from the address-signalling message having said target IP address as its source IP address, a MAC address of said terminal;
• generating, by the gateway, a firewall pinholing rule associated with said terminal identified by its MAC address;
• and
• deleting, by the gateway, the target IP address from the table managed by the gateway;
• determining, by the gateway, that the target IP address is not attributed to a terminal if no address-signalling message having said target IP address as its source IP address is received in response to the sending of the second address test message targeting said target IP address;
• and
• deleting, by the gateway, the target IP address from the table managed by the gateway when the predetermined number of second address test messages targeting said target IP address have been sent by the gateway without any address-signalling message received in return.