Method of IP address de-aliasing
View Patent ↗A method of internet protocol (IP) address de-aliasing that involves obtaining IP addresses from devices in a network, pinging pairs of the IP addresses by sending packets to pairs of the IP addresses, obtaining ping response orders for the packets, and determining whether the pairs of IP addresses are aliases of the same network device based on the obtained ping response orders.
1. A method of internet protocol (IP) address de-aliasing comprising:
a) obtaining IP addresses from devices in a network;
b) selecting a first pair of IP addresses, comprising a first IP address and a second IP address, from the obtained IP addresses;
c) pinging the first IP address and pinging the second IP address in a first order;
d) receiving a first ping response from the first IP address and receiving a second ping response from the second IP address;
e) determining a second order comprising an order of receipt of the first and second ping responses, wherein determining the second order comprises adjusting the second order to account for a delay between pinging the first IP address and pinging the second IP address;
f) repeating c-e a plurality of times;
g) determining a relationship between the first order and the second order; and
h) determining whether the first and second IP addresses are aliases of the same network device based on the relationship.
2. The method of claim 1 wherein determining the second order also comprises determining that the second ping response is received first if the second ping response is received less than a predetermined time after the first ping response.
3. The method of claim 1 wherein the delay between pinging the first IP address and pinging the second IP address is determined by kernel timestamping the first ping request to obtain a first ping sending time and kernel timestamping the second ping request to obtain a second ping sending time and determining a difference between the first and second ping sending times.
4. The method of claim 1 wherein determining a relationship comprises determining whether the second order is affected by the first order.
5. The method of claim 1 wherein determining a relationship comprises identifying the first pair of IP addresses as aliases when the second order is dependent on the first order.
6. The method of claim 5 wherein determining a relationship comprises identifying the first pair of IP addresses as belonging to different devices when the second order is independent of the first order.
7. The method of claim 1 including:
i) selecting a next pair of first and second IP addresses; and
j) performing c-e a plurality of times for the first and second IP addresses of the next pair of IP addresses;
k) determining a relationship between the first order and the second order for the next pair of IP addresses; and
l) determining whether the first and second IP addresses of the next pair of IP addresses are aliases of a single network device based on the relationship.
8. The method of claim 1 wherein pinging an IP address comprises sending a packet to the IP address and receiving a response and including determining a value A comprising a percentage of packets sent to the first IP address first that return first and a value B comprising a percentage of packets sent to the second IP address first that return first.
9. The method of claim 8 including determining a statistic S equal to (A×B)−[(1−A)×(1−B)] and determining the first and second IP addresses to be aliases when S has a first set of values.
10. The method of claim 9 wherein said first set of values comprises the complement of −0.45<S<0.45.
11. The method of claim 1 including obtaining round-trip time measurements from an endpoint to the IP addresses in the network and forming at least first and second groups of IP addresses based on the round trip time measurements.
12. The method of claim 11 wherein said selecting a first pair of IP addresses comprises selecting a first pair of IP addresses from within the first group.
13. The method of claim 1 ,
wherein determining a relationship comprises identifying the first pair of IP addresses as aliases when the second order is dependent on the first order, and
wherein pinging an IP address comprises sending a packet to the IP address and receiving a response and including determining a value A comprising a percentage of packets sent to the first IP address first that return first and a value B comprising a percentage of packets sent to the second IP address first that return first.
14. A non-transitory computer readable recording medium storing instructions for causing a computer to perform a method of:
a) obtaining IP addresses from devices in a network;
b) selecting a first pair of IP addresses, comprising a first IP address and a second IP address, from the obtained IP addresses;
c) pinging the first IP address and pinging the second IP address in a first order;
d) receiving a first ping response from the first IP address and receiving a second ping response from the second IP address;
e) determining a second order comprising an order of receipt of the first and second ping responses, wherein determining the second order comprises adjusting the second order to account for a delay between pinging the first IP address and pinging the second IP address;
f) repeating c-e a plurality of times;
g) determining a relationship between the first order and the second order; and
h) determining whether the first and second IP addresses are aliases of the same network device based on the relationship.
15. The non-transitory computer readable recording medium of claim 14 wherein determining the second order also includes determining a time delay d between pinging the first IP address and pinging the second IP address and determining the second ping response to be received before the first ping response if the second ping response is received less than the time d after the first ping response.