Dynamic initial congestion window modification

• US 10,326,703 B2
• Filed: 10/10/2017
• Issued: 06/18/2019
• Est. Priority Date: 12/05/2014
• Status: Active Grant

• Current Assignee: Edgio Incorporated
• Original Assignee: Verizon Digital Media Services Inc. (Verizon Communications Inc.)
• Inventors: Flores, Marcel Eric Schechner, Khakpour, Amir Reza, Peters, Robert J.
• Primary Examiner(s): Yao, Kwang B
• Assistant Examiner(s): Bokhari, Syed M
• Application Number:
  US15/729,489
• Publication Number:
  US 20180034742A1
• Time in Patent Office: 616 Days
• Field of Search: 370237, 370230, 370235
• CPC Class Codes: H04L 47/193 at the transport layer, e.g. TCP related
• CPC Class Codes: H04L 47/27 Evaluation or update of window size, e.g. using information derived from acknowledged [ACK] packets

Abstract

Some embodiments increase throughput across a connection between a host and a client by initializing the congestion window for that connection dynamically using a previously settled value from a prior instance of the connection established between the same or similar endpoints. An initialization agent tracks congestion window values for previously established connections between a host and various clients. For the tracked congestion window values of each monitored connection, the initialization agent stores an address identifying the client endpoint. When establishing a new connection, the initialization agent determines if the new connection is a recurring connection. A new connection is recurring when the new connection client address is similar or related to an address identified for a previous monitored connection. For a recurring connection, the initialization agent initializes the new connection congestion window using a value derived from the tracked congestion window values of the recurring connection.

Claims

1. A method comprising:

storing in memory of a particular server, a first congestion window value used in transmitting data packets over a first network connection to a first client device, wherein the first congestion window value is larger than a default initial congestion value used to initialize said first network connection;

establishing a different second network connection between the particular server and a second client, wherein said establishing comprises (i) initializing a congestion window of the second network connection with the first congestion window value from the first network connection in response to commonality in addressing between the first client and the second client, and (ii) initializing the congestion window of the second network connection with the default initial congestion window value in response to no commonality in the addressing between the first client and the second client;

regulating, with the first congestion window value, transmission of an initial set of data packets from the particular server to the second client over the second network connection in response to said commonality in addressing between the first client and the second client; and

regulating, with the default initial congestion value, transmission of said initial set of data packets from the particular server to the second client over the second network connection in response to no commonality in addressing between the first client and the second client.

2. The method of claim 1, wherein said initializing the congestion window of the second network connection with the first congestion window value comprises changing the default initial congestion value of the second network connection to the first congestion window value before transmission of a first data packet over the second network connection.

3. The method of claim 1, wherein said commonality in addressing between the first client and the second client comprises at least one of an address of the second client being the same as an address of the first client, or the address of the second client being in a specific subnet or range as the address of the first client.

4. The method of claim 1 further comprising terminating the first network connection with the first client prior to said establishing the different second network connection with the second client.

5. The method of claim 1 further comprising transmitting a plurality of data packets from the particular server to the first client over the first network connection, and tracking different congestion window values of the first network connection at different points in time during said transmitting.

6. The method of claim 5, wherein storing the first connection congestion window value comprises computing said first congestion window value from the different congestion window values resulting from said tracking.

7. The method of claim 1, wherein the default initial congestion value is the Transmission Control Protocol (TCP) default starting congestion window value.

8. A method comprising:

storing in memory of a particular server, a first congestion window value used in transmitting data packets over a first network connection to a first client device, wherein the first congestion window value is larger than a default initial congestion value used to initialize network connections according to a network protocol;

transmitting based on the first congestion window value, an initial first set of unacknowledged data packets from the particular server to a second client over a different second network connection in response to commonality in addressing between the first client and the second client, wherein the initial first set of unacknowledged data packets are transmitted from the particular server prior to the second client acknowledging any data packet in the initial first set of unacknowledged packets; and

transmitting based on the default initial congestion window value, an initial second set of unacknowledged data packets from the particular server to the second client over the second network connection in response to no commonality in addressing between the first client and the second client, wherein the initial first set of data packets transmitted based on the first congestion window value has more unacknowledged data packets than the initial second set of data packets transmitted based on the default initial congestion window value, and wherein the initial second set of unacknowledged data packets are transmitted from the particular server prior to the second client acknowledging any data packet in the initial second set of unacknowledged packets.

9. The method of claim 8 further comprising establishing the different second network connection with the second client prior to sending any data packets over the second network connection, wherein said establishing comprises overriding a congestion window value set by the Transmission Control Protocol (TCP) in response to commonality in the addressing between the first client and the second client, and retaining the congestion window value set by the TCP in response to no commonality in the addressing between the first client and the second client.

10. The method of claim 8, wherein storing the first congestion window value comprises storing a time-to-live (TTL) parameter with said first connection congestion window value.

11. The method of claim 10 further comprising establishing the different second network connection with the second client prior to sending any data packets over the second network connection, wherein said establishing comprises initializing the congestion window of the second network connection with the first connection congestion window value of the first connection in response to said commonality and the TTL parameter not expiring, and initializing the congestion window of the second connection with the default initial congestion window value in response to said commonality and the TTL parameter expiring.

12. A method comprising:

establishing a first network connection prior to passing a first data packet over said first network connection, wherein said establishing the first network comprises initializing a congestion window of the first network connection with a first congestion window value from a different second network connection;

initiating transmission of data packets over the first network connection by sending a first number of unacknowledged data packets based on said first congestion window value;

establishing a third network connection prior to passing a first data packet over said third network connection, wherein said establishing the third network connection comprises initializing a congestion window of the third network connection with a different second congestion window value from a different fourth network connection; and

initiating transmission of data packets over the third network connection by sending a different second number of unacknowledged data packets based on said second congestion window value, wherein the second number of unacknowledged data packets is greater than the first number of unacknowledged data packets.

13. The method of claim 12, wherein the first congestion window value and the second congestion window value are different than a default starting Transmission Control Protocol (TCP) congestion window value.

14. The method of claim 12, wherein the first number of unacknowledged data packets and the second number of unacknowledged data packets are greater than a starting number of unacknowledged data packets defined by TCP.

15. The method of claim 12, wherein the second network connection is terminated prior to said establishing the first network connection, and wherein the fourth network connection is terminated prior to said establishing the third network connection.

16. The method of claim 12 further comprising identifying commonality in addressing between endpoints of the first and second network connections during said establishing the first network connection, and identifying commonality in addressing between endpoints of the third and fourth network connections during said establishing the third network connection.

17. The method of claim 12 further comprising adjusting the first congestion window value while passing a plurality of data packets over the second network connection.

18. A device comprising:

a non-transitory computer-readable medium storing a set of processor-executable instructions; and

one or more processors configured to execute the set of processor-executable instructions, wherein executing the set of processor-executable instructions causes the one or more processors to;

store in the non-transitory computer-readable medium, a first congestion window value used in transmitting data packets over a first network connection to a first client device, wherein the first congestion window value is larger than a default initial congestion value used to initialize network connections according to Transmission Control Protocol (TCP);

establish a different second network connection with a second client prior to sending any data packets over the second network connection, wherein said establishing comprises processor-executable instructions to;

override a congestion window value set by the TCP in response to commonality in the addressing between the first client and the second client, and

retain the congestion window value set by the TCP in response to no commonality in the addressing between the first client and the second client;

transmit based on the first congestion window value, an initial first set of unacknowledged data packets to the second client over a different second network connection in response to commonality in addressing between the first client and the second client; and

transmit based on the default initial congestion window value, an initial second set of unacknowledged data packets to the second client over the second network connection in response to no commonality in addressing between the first client and the second client, wherein the initial first set of data packets transmitted based on the first congestion window value has more unacknowledged data packets than the initial second set of data packets transmitted based on the default initial congestion window value.