Remote identification of client and DNS proxy IP addresses

An apparatus for identifying an address of a network element that a particular client uses to obtain IP addresses, comprising:

• an interface coupled to a network to receive client messages, and
• a processor coupled to the interface, the processor executing a set of computer program instructions, the computer program instructions:
• receiving a request from a network element in response to the network element receiving a test message destined for a test URL from a client, the test URL including a host name at least in part distinguishable from host names in non-test URLs according to a predetermined uniqueness and not known to the client or network element but for which the apparatus is known to be authoritative;
• and
• recognizing the predetermined uniqueness in the host name of the test URL in the request from the network element to resolve the host name to an IP address and responsively (i) distinguishing the request from requests including non-test URLs, (ii) identifying the address of the network element used by the client to obtain the IP address, and (iii) registering the network element making the request.

A computer program product comprising:

• a computer usable medium for storing data;
• and
• a set of computer program instructions embodied on the computer useable medium, including instructions to:
• receive a request from a network element in response to the network element receiving a test message destined for a test URL from a client, the test URL including a host name at least in part distinguishable from host names in non-test URLs according to a predetermined uniqueness and not known to the client or network element but for which a server executing the computer program instructions is known to be authoritative;
• and
• recognize the predetermined uniqueness in the host name in the test URL received in the request from the network element to resolve the host name to an IP address and responsively (i) distinguishing the request from requests including non-test URLs, (ii) identifying the address of the network element used by the client to obtain the IP address, and (iii) registering the address of the network element making the request.

A method for assisting to identify an address of a network element that a particular client uses to obtain IP addresses, comprising:

• receiving a message from a client;
• parsing the message for an IP address of the client and encoding the client IP address into a host name for a test URL, the test URL including the host name not known to the client or network element used by the client but for which a test server is authoritative;
• and
• returning the test URL to the client in a redirect test message, the redirect test message causing the client to send a non-redirect test message to the network element to make a request of the test server to resolve the host name in the test URL to a test IP address.

An apparatus for identifying an address of a network element that a particular client uses to obtain IP addresses, comprising:

• means for receiving a message from a client;
• means for parsing the message for an IP address of the client and encoding the client IP address into a host name for a test URL, the test URL including the host name not known to the client or network element used by the client but for which a test server is authoritative;
• and
• means for forwarding the test URL back for the client in a redirect test message, the redirect test message causing the client to send a non-redirect test message to the network element to make a request of the server to resolve the host name in the test URL to a test IP address.