METHOD AND APPARATUS FOR DETERMINING MAXIMUM ROUND TRIP TIMES FOR A NETWORK SOCKET

• US 20080056146A1
• Filed: 08/29/2006
• Published: 03/06/2008
• Est. Priority Date: 08/29/2006
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Gupta, Nikhil, Lazzaro, Christopher Victor, Elliott, Steven L.
• Application Number:
  US11/468,161
• Publication Number:
  US 20080056146A1
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 43/0864 Round trip delays
• CPC Class Codes: H04L 43/50 Testing arrangements
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/25 with rate being modified by the source upon detecting a change of network conditions
• CPC Class Codes: H04L 47/283 in response to processing delays, e.g. caused by jitter or round trip time [RTT]
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures

Abstract

A computer implemented method, apparatus, and computer usable program code for identifying a maximum round trip time over a socket for use in transmitting data over a connection. During a beginning phase of a send operation through a socket, packets are sent on the connection as fast as possible. The as fast as possible value is determined by the network and an event is generated that flows back to the application. Sending of the packets is halted in response to this event. Round trip times for the packets sent are identified by waiting for the acknowledgement for the packets sent. The maximum round trip time from the various round trip times is identified, wherein the maximum round trip time used in an adaptive bandwidth control algorithm to determine the optimum rate of sending the data to the endpoint.

Claims

1. A computer implemented method for identifying a maximum round trip time over a socket for use in transmitting data over a connection, the computer implemented method comprising:

during a beginning of a send operation through a socket, sending packets as fast as possible on the connection to an endpoint;

halting sending of the packets in response to an event;

identifying round trip times for the packets, which were sent; and

identifying the maximum round trip time from the round trip times, wherein the maximum round trip time used in sending the data to the endpoint.

2. The computer implemented method of claim 1, wherein the event is selected from one of an elapse of a selected time period, receipt of a signal that additional data cannot be written to the socket.

3. The computer implemented method of claim 1, wherein the computer implemented method is implemented in a transport layer.

4. The computer implemented method of claim 1 further comprising:

sending the data to the endpoint using the maximum round trip time.

5. The computer implemented method of claim 1, wherein the step of identifying round trip times for the packets which were sent comprises:

waiting for an acknowledgement a sent packet;

identifying a round trip time when the acknowledgment is received for the sent packet; and

repeating the waiting and identifying steps until all acknowledgements for sent packets are received.

6. The computer implemented method of claim 1, wherein the endpoint is a computer.

7. The computer implemented method of claim 1, wherein the event is one of a specified time period, a presence of stable round trip time measurements, a specified number of packets has been sent, or a specified amount of data has been sent.

8. A computer program product comprising:

a computer usable medium having computer usable program code for identifying a maximum round trip time over a socket for use in transmitting data over a connection, the computer program medium comprising;

computer usable program code, during a beginning of a send operation through a socket, sending packets as fast as possible on the connection to an endpoint;

computer usable program code for halting sending of the packets in response to an event;

computer usable program code for identifying round trip times for the packets, which were sent; and

computer usable program code for identifying the maximum round trip time from the round trip times, wherein the maximum round trip time used in sending the data to the endpoint.

9. The computer program product of claim 8, wherein the event is selected from one of an elapse of a selected time period, receipt of a signal that additional data cannot be written to the socket.

10. The computer program product of claim 8, wherein the computer program product is for a transport layer.

11. The computer program product of claim 8 further comprising:

computer usable program code for sending the data to the endpoint using the maximum round trip time.

12. The computer program product of claim 8, wherein the step of identifying round trip times for the packets which were sent comprises:

computer usable program code for waiting for an acknowledgement a sent packet;

computer usable program code for identifying a round trip time when the acknowledgment is received for the sent packet; and

computer usable program code for repeating the waiting and identifying steps until all acknowledgements for sent packets are received.

13. The computer program product of claim 8, wherein the endpoint is a computer.

14. The computer program product of claim 8, wherein the event is one of a specified time period, a presence of stable round trip time measurements, a specified number of packets has been sent, or a specified amount of data has been sent.

15. A data processing system comprising:

a bus;

a communications unit connected to the bus;

a storage device connected to the bus, wherein the storage device includes computer usable program code; and

a processor unit connected to the bus, wherein the processor unit executes the computer usable program code to identify a maximum round trip time over a socket for use in transmitting data over a connection;

during a beginning of a send operation through a socket, send packets as fast as possible on the connection to an endpoint;

halt sending of the packets in response to an event;

identify round trip times for the packets, which were sent; and

identify the maximum round trip time from the round trip times, wherein the maximum round trip time used in sending the data to the endpoint.

16. The data processing system of claim 15, wherein the event is selected from one of an elapse of a selected time period, receipt of a signal that additional data cannot be written to the socket.

17. The data processing system of claim 15, wherein the processor unit further executes the computer usable program code to send the data to the endpoint using the maximum round trip time.

18. The data processing system of claim 15, wherein in executing the computer usable program code to identify round trip times for the packets which were sent comprises:

the processor executes the computer usable program code to wait for an acknowledgement a sent packet;

identify a round trip time when the acknowledgment is received for the sent packet; and

repeat the waiting and identifying steps until all acknowledgements for sent packets are received.

19. The data processing system of claim 15, wherein the endpoint is a computer.

20. The data processing system of claim 15, wherein the event is one of a specified time period, a presence of stable round trip time measurements, a specified number of packets has been sent, or a specified amount of data has been sent.