HTTP STREAMING CLIENT ADAPTATION ALGORITHM BASED ON PROPORTIONAL-INTEGRAL CONTROL

• US 20150067105A1
• Filed: 08/28/2013
• Published: 03/05/2015
• Est. Priority Date: 08/28/2013
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Zhu, Xiaoqing, Li, Zhi, Pan, Rong, Gahm, Joshua B., Hu, Hao
• Granted Patent: US 9,485,289 B2
• Time in Patent Office: Days
• US Class Current: 709/219
• CPC Class Codes: H04L 47/25 with rate being modified by the source upon detecting a change of network conditions
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/38 by adapting coding or compression rate
• CPC Class Codes: H04L 65/60 Network streaming of media packets
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/75 Media network packet handling
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]

Abstract

In one embodiment, an HTTP streaming session may be initiated at a client device in a network. The client device may have a buffer and may be configured to request and receive one or more data segments over HTTP from an HTTP server. A first data segment at a first data source rate may be requested and subsequently received. The first data segment may be stored in the buffer. A second data source rate may then be calculated based on a storage level in the buffer, and a second data segment at the second data source rate may be requested.

Claims

1. A method, comprising:

initiating, at a client device in a network, a Hyper-Text Transfer Protocol (HTTP) streaming session, wherein the client device has a buffer and is configured to request and receive one or more data segments over HTTP from an HTTP server;

requesting a first data segment at a first data source rate;

receiving the first data segment at the first data source rate;

storing the first data segment in the buffer;

calculating a second data source rate based on a storage level in the buffer; and

requesting a second data segment at the second data source rate.

2. The method as in claim 1, further comprising:

calculating the second data source rate and requesting the second data segment at the second data source rate substantially immediately after the first data segment is requested.

3. The method as in claim 1, wherein the calculating of the second data source rate is further based on a predetermined reference storage level in the buffer.

4. The method as in claim 1, wherein the calculating of the second data source rate is further based on the first data source rate.

5. The method as in claim 1, wherein the second data source rate is calculated according to a client adaptation algorithm based on proportional-integral (PI) control.

6. The method as in claim 1, wherein the second data source rate is calculated according to the following formula:

R=R_last+kappa*(L−

L_o)+eta*(L−

L_last),

wherein;

R is the second data source rate,

R_last is the first data source rate,

L is the storage level in the buffer,

L_o is a predetermined reference storage level in the buffer,

L_last is a previous storage level in the buffer,

kappa is a first predetermined scaling parameter, and

eta is a second predetermined scaling parameter.

7. The method as in claim 6, further comprising:

adjusting one or more of;

the first predetermined scaling parameter and the second predetermined scaling parameter.

8. The method as in claim 1, wherein the first data segment and the second data segment are a first video segment and a second video segment, respectively.

9. The method as in claim 1, further comprising:

determining a buffer playout duration based on the storage level in the buffer.

10. The method as in claim 1, wherein:

the client device is engaged in the HTTP streaming session while a plurality of other client devices in the network are engaged in respective HTTP streaming sessions, and

the client device and the plurality of other client devices receive data segments over a shared communications link.

11. The method as in claim 1, further comprising:

determining whether the buffer is full, wherein the second data segment is requested only when the buffer is not full.

12. An apparatus, comprising:

one or more network interfaces that communicate with a network;

a processor coupled to the one or more network interfaces and configured to execute a process; and

a memory configured to store program instructions which contain the process executable by the processor, the process comprising;

initiating, as a client device in the network, a Hyper-Text Transfer Protocol (HTTP) streaming session, wherein the client device has a buffer and is configured to request and receive one or more data segments over HTTP from an HTTP server;

requesting a first data segment at a first data source rate;

receiving the first data segment at the first data source rate;

storing the first data segment in the buffer;

calculating a second data source rate based on a storage level in the buffer; and

requesting a second data segment at the second data source rate.

13. The apparatus as in claim 12, wherein the process further comprises:

calculating the second data source rate and requesting the second data segment at the second data source rate substantially immediately after the first data segment is requested.

14. The apparatus as in claim 12, wherein the calculating of the second data source rate is further based on a predetermined reference storage level in the buffer.

15. The apparatus as in claim 12, wherein the calculating of the second data source rate is further based on the first data source rate.

16. The apparatus as in claim 12, wherein the second data source rate is calculated according to a client adaptation algorithm based on proportional-integral (PI) control.

17. The apparatus as in claim 12, wherein the second data source rate is calculated according to the following formula:

R=R_last+kappa*(L−

L_o)+eta*(L−

L_last), wherein;

R is the second data source rate,

R_last is the first data source rate,

L is the storage level in the buffer,

L_o is a predetermined reference storage level in the buffer,

L_last is a previous storage level in the buffer,

kappa is a first predetermined scaling parameter, and

eta is a second predetermined scaling parameter.

18. The apparatus as in claim 17, wherein the process further comprises:

adjusting one or more of;

the first predetermined scaling parameter and the second predetermined scaling parameter.

19. The apparatus as in claim 12, wherein the first data segment and the second data segment are a first video segment and a second video segment, respectively.

20. The apparatus as in claim 12, wherein the process further comprises:

determining a buffer playout duration based on the storage level in the buffer.

21. The apparatus as in claim 12, wherein:

the client device is engaged in the HTTP streaming session while a plurality of other client devices in the network are engaged in respective HTTP streaming sessions, and

the client device and the plurality of other client devices receive data segments over a shared communications link.

22. The apparatus as in claim 12, wherein the process further comprises:

determining whether the buffer is full, wherein the second data segment is requested only when the buffer is not full.

23. A tangible non-transitory computer readable medium storing program instructions that cause a computer to execute a process, the process comprising:

initiating an HTTP streaming session at a client device in a network, wherein the client device has a buffer and is configured to request and receive one or more data segments over HTTP from an HTTP server;

requesting a first data segment at a first data source rate;

receiving the first data segment at the first data source rate;

storing the first data segment in the buffer;

calculating a second data source rate based on a storage level in the buffer; and

requesting a second data segment at the second data source rate