Apparatus and methods for mitigating protocol-induced back-offs in a communication network

• US 20130244590A1
• Filed: 06/27/2012
• Published: 09/19/2013
• Est. Priority Date: 03/19/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Nukala, Gaurav, Deivasigamani, Giri Prassad, Alam, Muhammad A.
• Granted Patent: US 8,843,175 B2
• Time in Patent Office: Days
• US Class Current: 455/77
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures
• CPC Class Codes: H04W 28/0278 using buffer status reports dynamic wireless traffic scheduling definition H04W72/12
• CPC Class Codes: H04W 28/10 Flow control between communication endpoints
• CPC Class Codes: H04W 76/16 Involving different core network technologies, e.g. a packet-switched [PS] bearer in combination with a circuit-switched [CS] bearer
• CPC Class Codes: H04W 76/34 Selective release of ongoing connections
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 80/06 Transport layer protocols, e.g. TCP [Transport Control Protocol] over wireless transmission control protocol/Internet protocol [TCP/IP] or user datagram protocol [UDP] H04L69/16
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Methods and apparatus for mitigating data server time-outs in e.g., a hybrid wireless network. In one exemplary embodiment, a client device operating in a hybrid network environment utilizes its knowledge about tune-away periods so as to minimally affect data network operation. For example, during periods of data downlink activity, the client device induces some delay in the acknowledgement packets sent back towards the network prior to entering into a tune away period. These delayed acknowledgement packets result in an increased retransmission time out period value thereby reducing the probability of encountering a data server time-out. Alternative embodiments are also discussed which preoccupy the network apparatus during these tune away periods so as to also mitigate time-outs during these periods. These mitigation algorithms are useful in both downlink and uplink data transmissions. Apparatus for implementing these methodologies are also disclosed.

Claims

1. Mobile wireless apparatus, comprising:

a first air interface configured to communicate with a first wireless network; and

logic in data communication with the first air interface, the logic configured to;

determine when the first air interface is to be tuned away from; and

implement a function which at least reduces the chance that a network-side server utilizing the first air interface to transfer data to the mobile device will adversely alter its operation regarding delivery of the data.

2. The apparatus of claim 1, further comprising a second air interface configured to communicate with a second wireless network.

3. The apparatus of claim 2, wherein the first air interface comprises a long term evolution (LTE) enabled interface, and the second air interface comprises a code division multiple access (CDMA) based interface.

4. The apparatus of claim 2, wherein the tuning away from the first air interface is performed in order to maintain at least one aspect of operation of the second air interface.

5. The apparatus of claim 1, wherein the data comprises data sent utilizing a transport protocol, and the adverse alteration of operation of the network-side server comprises timing out within the transport protocol based on a lack of one or more received acknowledgements from the mobile apparatus.

6. The apparatus of claim 5, wherein the timing out causes undesirable latency in delivery of the data to the mobile apparatus.

7. The apparatus of claim 1, wherein the function comprises imposing a delay on acknowledgement messages to be sent to the network side server during transmission of the data.

8. The apparatus of claim 1, wherein the function comprises reducing a fill limit associated with at least one data buffer maintained by the mobile apparatus.

9. The apparatus of claim 1, wherein the function comprises reducing an uplink resource allocation transmitted to the first wireless network.

10. The apparatus of claim 9, wherein the resource allocation transmitted to the first wireless network is transmitted using at least one of (i) a buffer status report (BSR) and/or (ii) a power headroom report (PHR).

11. A method for reducing the likelihood of encountering a data server time-out during transmission of data to a client device, the method comprising:

executing a data access technology;

determining when the client device is to enter into a tune away period; and

prior to entering the tune away period, executing a mitigation algorithm on the client device so as to reduce the likelihood of encountering a data server time-out.

12. The method of claim 11, wherein the data access technology comprises a high-speed wireless cellular data access technology that is optimized for data transfer.

13. The method of claim 12, wherein the optimization for data transfer comprises an optimization for Internet Protocol (IP)-based data.

14. The method of claim 11, wherein the data server comprises a transport control protocol (TCP) enabled server, and the time-out comprises a TCP-based timeout based at least on lack or receiving one or more acknowledgement messages initiated by the client device.

15. The method of claim 11, wherein the tune away period comprises a period scheduled to allow the client device to maintain a connection to a wireless network.

16. The method of claim 15, wherein the wireless network comprises a different network than that used for the data access technology.

17. Mobile wireless apparatus, comprising:

a first air interface configured to communicate with a first wireless network; and

logic in data communication with the first air interface, the logic configured to;

determine when the first air interface is to be tuned away from for a period of time; and

cause transmission of a message or signal to a network-side server utilizing the first air interface to transfer data to the mobile apparatus to cause the server to implement a function which at least reduces the chance that the server will adversely alter its operation regarding delivery of the data at least during the tune away period.

18. The apparatus of claim 17, wherein the message or signal is transmitted before the tune away period commences.

19. The apparatus of claim 17, wherein the message or signal is transmitted after the tune away period commences but before an acknowledgement message is required to be sent from the mobile apparatus pursuant to the delivery of the data.

20. The apparatus of claim 17, wherein the function comprises imposing a delay on invoking a timeout condition within the server due to failure to receive one or more acknowledgement messages from the mobile apparatus.

21. The apparatus of claim 17, wherein the function comprises adjusting the delivery of the data to the mobile apparatus for at least a period of time such that acknowledgement messages are required less frequently during at least the period of time.

22. A method of operating a data server during transmission of data to a client device, the method comprising:

delivering data from the server to the client device via a wireless data access technology;

determining when the client device is to tune away from the data access technology; and

prior to the tune away, executing a mitigation function on the data server so as to reduce the likelihood of an interruption in the delivery of the data by the server.

23. The method of claim 22, wherein the data server comprises a transport control protocol (TCP) enabled server, and the interruption comprises the server timing out due to lack of response from the client device.