Dynamic Throttling Based on Network Conditions

• US 20090319681A1
• Filed: 06/20/2008
• Published: 12/24/2009
• Est. Priority Date: 06/20/2008
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Freelander, Jack E., Sood, Vishal, Knowlton, Christopher G., Zhang, Geqiang
• Granted Patent: US 8,239,564 B2
• Time in Patent Office: Days
• US Class Current: 709/233
• CPC Class Codes: H04L 47/25 with rate being modified by the source upon detecting a change of network conditions
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements

Abstract

The dynamic management of download rates when downloading digital resources to clients. A server concurrently maintains download sessions with any number of clients, each download session for downloading a corresponding digital resource to a corresponding client. The download rates for the various download sessions are adjusted as download sessions are completed, and as new download sessions are added. As new download sessions are initiated, a minimum and target download rate may be calculated. The target download rate is the rate at which the server will attempt to download the requested digital resource to the client, and will depend on the total available bandwidth for use to download the digital resources.

Claims

1. A method for a server to manage download rates when the server downloads digital resources to a plurality of clients, the method comprising:

an act of receiving a request to download a particular digital resource to a particular client;

an act of determining a minimum download rate to use when downloading the particular digital resource to the particular client; and

an act of calculating a target download rate to attempt to use when downloading the particular digital resource to the particular client, the calculated target download rate based at least upon an estimate of a total available server bandwidth.

2. A method in accordance with claim 1, wherein the calculated target download rate is also based upon one or more parameters of the particular digital resource.

3. A method in accordance with claim 2, wherein the one or more parameters of the particular digital resource includes a file type of the particular digital resource.

4. A method in accordance with claim 2, wherein the one or more parameters of the particular digital resource include a file size of the particular resource.

5. A method in accordance with claim 1, wherein the calculated target download rate is also based on a state of one or more concurrent download sessions that the server is presently supporting.

6. A method in accordance with claim 1, wherein the calculated target download rate is also based on the minimum download rate for the particular resource.

7. A method in accordance with claim 6, wherein the calculated target download rate is proportional to the minimum download rate for the particular resource.

8. A method in accordance with claim 5, further comprising:

an act of adjusting the download rates of the one or more concurrent download sessions downwards to accommodate bandwidth for the particular digital resource to be downloaded to the particular client.

9. A method in accordance with claim 1, wherein the act of determining a minimum download rate to use when downloading the particular digital resource to the particular client comprises:

an act of identifying a file type of the particular resource, wherein the minimum download rate is directly specified by configuration data.

10. A method in accordance with claim 1, wherein the act of determining a minimum download rate to use when downloading the particular digital resource to the particular client comprises:

an act of identifying an encoded bit rate of the particular digital resource;

an act of identifying a file type of the particular resource; and

an act of calculating the minimum download rate using the encoded bit rate of the particular digital resource.

11. A method in accordance with claim 1, further comprising:

an act of attempting to download the particular digital resource to the particular client at the calculated target download rate.

12. A method in accordance with claim 11, further comprising:

if the attempt was unsuccessful, an act of reducing a download rate to somewhere between the calculated target download rate and the minimum download rate.

13. A method in accordance with claim 1, further comprising:

an act of determining whether the calculated target download rate is greater than the minimum download rate for the particular digital resource;

if the calculated target download rate is greater than the minimum download rate, an act of attempting to download the particular digital resource to the particular client at the calculated target download rate; and

if the calculated target download rate is less than the minimum download rate, an act of refraining from granting the request to download the particular digital resource.

14. A computer program product comprising one or more computer-readable media having thereon one or more computer-executable instructions that, when executed by one or more processors of a computing system, cause the computing system to perform a method for managing download rates when the server downloads digital resources to a plurality of clients, the method comprising:

an act of concurrently maintaining a plurality of download sessions with a plurality of download clients, each download session for downloading a corresponding digital resource to a corresponding client, wherein the plurality of download sessions are maintained using at least a majority of a predetermined portion of the total available server bandwidth; and

an act of adjusting downwards the download rates of at least one of the maintained download sessions when a new download session is to be initiated by the server.

15. A computer program product in accordance with claim 14, wherein the one or more computer-readable media are physical memory and/or storage media.

16. A computer program product in accordance with claim 15, wherein the method further comprises:

an act of adjusting upwards the download rate of at least one of the maintained download sessions when a maintained download session is completed.

17. A computer program product in accordance with claim 15, wherein the method further comprises:

an act of determining a minimum download rate to use in the new download session; and

an act of calculating a target download rate to attempt to use in the new download, the calculated target download rate based at least upon an estimate of the total available server bandwidth.

18. A computer program product in accordance with claim 15, wherein the plurality of download sessions are for downloading media files that have an encoded bit rate, as well as other files that do not have an encoded bit rate.

19. A computer program product comprising one or more computer-readable media having thereon one or more computer-executable instructions that, when executed by one or more processors of a computing system, cause the computing system to perform a method for managing download rates when the server downloads digital resources to a plurality of clients, the method comprising:

an act of concurrently maintaining a plurality of download sessions with a plurality of download clients, each download session for downloading a corresponding digital resource to a corresponding client, wherein the plurality of download sessions are maintained using at least a majority of a total available server bandwidth;

while concurrently maintaining the plurality of download sessions, an act of receiving a request to download a particular digital resource to a particular client;

an act of determining a minimum download rate to use when downloading the particular digital resource to the particular client; and

an act of calculating a target download rate to attempt to use when downloading the particular digital resource to the particular client, the calculated target download rate based at least upon an estimate of the total available server bandwidth, a type of the particular digital resource file, and on the download rates of the plurality of download clients.

20. A computer program product in accordance with claim 19, wherein the one or more computer-readable media are physical memory and/or storage media.