Measuring delays from content servers to network devices on paths to a client such as for use in selecting a content server based on a common network device

A method, comprising:

• sending a plurality of packets from a source to a client over a network with each of the plurality of packets including a different time to live, and the network including a plurality of network devices;
• receiving indications from a plurality of different network devices of said network devices that the plurality of packets were dropped;
• for each particular packet of the plurality of packets sent to the client and for which an indication was received from one of the plurality of different network devices that said particular packet was dropped, measuring the time from sending said particular packet to receiving a corresponding said received indication that said particular packet was dropped in order to determine the delay between the plurality of different network devices and the source along a path between the source and the client;
• and
• performing said operations of sending the plurality of packets, receiving said indications and said measuring the time for each particular packet for each of a first source being the source and a second source being a source;
• comparing the network devices identified by said operations for the first and second source to identify a common network device of said different network devices common to both the path from the first source to the client and the second source to the client;
• and comparing said measured time from the first source to the common network device and said measured time from the second source to common network device to identify the relative closeness of the first and second sources to the client.

An apparatus comprising:

• means for initiating a measurement operation for each particular content server of a plurality of mirrored content servers in a network to determine a plurality of delay-measured network devices and time delays to each of the plurality of delay-measured network devices among a respective path between a client and the particular content server;
• means for receiving and analyzing an identification of, and measured time delays to, the plurality of delay-measured network devices for each of the plurality of mirrored content servers in order to:
• identifying a particular delay-measured network device from said pluralities of delayed measured devices that is common to each of said respective paths between the client and the plurality of mirrored content servers;
• and select one of the plurality of mirrored content servers based on a corresponding least value of said measured time delays to the particular delay-measured network device;
• and
• means for communicating an indication of said selected content server to the client or said selected content server in response to said selection of one of the plurality of mirrored content servers.

An apparatus, comprising,

• one or more processors and memory configured for storing one or more instructions that, when executed by said one or more processors, perform operations, with the apparatus being in a network including a client, a plurality of content servers, and network devices along a plurality of different paths between the client and the plurality of content servers, with said operations comprising:
• initiating a measurement operation for each particular content server of the plurality of content servers to determine a plurality of delay-measured network devices and time delays to each of the plurality of delay-measured network devices among a respective path of the plurality of different paths, with the respective path being between the client and the particular content server;
• and
• receiving and analyzing an identification of, and measured time delays to, the plurality of delay-measured network devices for each of the plurality of content servers in order to:
• identifying a particular delay-measured network device from said pluralities of delayed measured devices that is common to each of said respective paths between the client and the plurality of content servers;
• and select one of the plurality of content servers based on a corresponding least value of said measured time delays to the particular delay-measured network device.