Data communications employing packet report messages

A method of operating a second endpoint system connected to a first endpoint system by a communications link on which the first endpoint system sends packets to the second endpoint system, the packets including respective sequence numbers reflecting a sequential order of transmission of the packets, the method comprising:

• identifying respective reception times for the packets, and storing, for each received packet, the respective sequence number and reception time;
• and
• sending packet report messages to the first endpoint system for respective received packets, each packet report message identifying (i) a received packet by its position within the sequential order of transmission of the packets, and (ii) the reception time of the received packet,
• wherein the first and second endpoints implement a logical connection using an application-level transport on the communications link, and wherein the packets are of the application-level transport and are structured to include a control portion and a channel portion, and wherein (1) the first endpoint system sends application data to the second endpoint system in the channel portion of the packets sent to the second endpoint system, and (2) the second endpoint system sends the packet report messages to the first endpoint system as control messages in the control portion of packets sent from the second endpoint system to the first endpoint system,
• and wherein the packet report messages have structure including a variable number of reports along with a report-count identifying a number of reports included in a respective packet report message, each report identifying a respective received packet and the reception time thereof.

A method of operating a first endpoint system connected to a second endpoint system by a communications link on which the first endpoint system sends packets to the second endpoint system, the packets including respective sequence numbers reflecting a sequential order of transmission of the packets, the method comprising:

• receiving the packet report messages from the second endpoint system for respective packets received by the second endpoint system, each packet report message identifying (i) a received packet by its position within the sequential order of transmission of the packets, and (ii) the reception time of the received packet;
• and
• processing the packet report messages to (i) detect missing packets sent to the second endpoint system and not identified as received in the packet report messages, and initiating re-transmission of the missing packets, and (ii) based on the reception times for the received packets, calculate one or more time-based performance characteristics for the communications link for use in higher-level control of usage of the communications link,
• wherein the first and second endpoints implement a logical connection using an application-level transport on the communications link, and wherein the packets are of the application-level transport and are structured to include a control portion and a channel portion, and wherein (1) the first endpoint system sends application data to the second endpoint system in the channel portion of the packets sent to the second endpoint system, and (2) the second endpoint system sends the packet report messages to the first endpoint system as control messages in the control portion of packets sent from the second endpoint system to the first endpoint system,
• and wherein the packet report messages have structure including a variable number of reports along with a report-count identifying a number of reports included in a respective packet report message, each report identifying a respective received packet and the reception time thereof.