Patent ID: 8166163

Claim:
A method comprising: accessing an operational criterion used to select a server; identifying, based on the operational criterion, a plurality of servers, wherein each server in the plurality of servers meets the operational criterion at a time the respective server was last contacted; obtaining an Internet Protocol (IP) address of each server in the plurality of servers; constructing a probe packet including a list of IP addresses of the plurality of servers, wherein a IP address of each server is listed in an order, a first and a last IP addresses in the list being IP addresses of a device generating the probe packet and wherein the probe packet includes instructions on processing the probe packet by a server that receives the probe packet; sending the probe packet to a first server whose IP address is a second IP address in the list of IP addresses in the probe packet; receiving an acknowledgement message from the first server, wherein the acknowledgment message is sent by the first server based on receiving at the first server another acknowledgment message from a second server whose IP address is immediately following the IP address of the first server in the list of IP addresses in the probe packet, and wherein the acknowledgement message received from the first server indicates successful reception of the probe packet by each of the plurality of servers associated with IP addresses included in the list; and determining, based on receiving the acknowledgement message from the first server, that the plurality of servers associated with IP addresses included in the list meet the operational criterion.