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

• US 8,843,175 B2
• Filed: 06/27/2012
• Issued: 09/23/2014
• 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.
• Primary Examiner(s): Trinh, Sonny
• Application Number:
  US13/535,194
• Publication Number:
  US 20130244590A1
• Time in Patent Office: 818 Days
• Field of Search: 370/328, 370/329, 370/341, 370/342, 370/345, 455/450, 455/509, 455/464, 455/434, 455/552.1, 455/515
• US Class Current: 455/552.1
• 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. A mobile wireless apparatus, comprising:

one or more processors;

at least one air interface configurable to communicate via a first wireless network or a second wireless network; and

a non-transitory computer-readable medium storing executable instructions, that when executed by the one or more processors, causes the mobile wireless apparatus to;

determine when to tune away the at least one air interface from the first wireless network to the second wireless network; and

prior to tuning away the at least one air interface, implement a function that reduces a likelihood that a network server will adversely alter an operation of the network server when transferring data to the mobile wireless apparatus using a transport protocol,

wherein the adverse alteration of the operation of the network server is associated with the network server timing out within the transport protocol based at least in part on the network server not receiving one or more acknowledgements from the mobile wireless apparatus.

2. The mobile wireless apparatus of claim 1, wherein the first wireless network is a long term evolution (LTE) compliant network, and the second wireless network is a code division multiple access (CDMA) compliant network.

3. The mobile wireless apparatus of claim 1, wherein the tune away from the first wireless network to the second wireless network is performed in order to maintain communication continuity for the mobile wireless apparatus.

4. The mobile wireless apparatus of claim 1, wherein the timing out of the network server causes an undesirable latency in transferring the data to the mobile wireless apparatus.

5. The mobile wireless apparatus of claim 1, wherein the function comprises imposing a delay in sending acknowledgement messages from the mobile wireless apparatus to the network server during the transmission of the data.

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

7. The mobile wireless apparatus of claim 1, wherein the function comprises reducing an uplink resource allocation of the mobile wireless apparatus for communicating via the first wireless network.

8. The mobile wireless apparatus of claim 7, wherein the uplink resource allocation of the mobile wireless apparatus for communicating via the first wireless network is transmitted using at least one of:

(i) a buffer status report (BSR); and

(ii) a power headroom report (PHR).

9. A method for reducing a likelihood of a network server time-out during a data transfer to a mobile device from the network server, the method comprising:

at the mobile device;

employing at least one air interface;

determining when to tune away the at least one air interface from a first wireless network to a second wireless network; and

prior to tuning away the at least one air interface, executing a mitigation algorithm to reduce a likelihood of the network server experiencing a transfer protocol time-out during the data transfer based at least in part on the network server not receiving one or more acknowledgement messages from the mobile device.

10. The method of claim 9, wherein the at least one air interface is associated with a high-speed wireless cellular data access technology that is optimized for transferring large amounts of Internet Protocol (IP)-based data.

11. The method of claim 9, wherein the tune away of the at least one air interface from the first wireless network to the second wireless network allows the mobile device to maintain communication continuity.

12. The method of claim 9, wherein the first wireless network is a long term evolution (LTE) compliant network, and the second wireless network is a code division multiple access (CDMA) compliant network.

13. A mobile wireless apparatus, comprising:

one or more processors;

at least one air interface configurable to communicate via a first wireless network or a second wireless network; and

a non-transitory computer-readable medium storing executable instructions, that when executed by the one or more processors, causes the mobile wireless apparatus to;

determine when to tune away the at least one air interface from the first wireless network to the second wireless network for a period of time;

and

transmit a message or a signal to a network server to cause the network server to transfer data associated with previously transferred data to the mobile wireless apparatus to cause the network server to implement a function that reduces a likelihood that the network server will adversely alter an operation of the network server associated with a data transmission to the mobile wireless apparatus during the tune away,

wherein the mobile wireless apparatus transmits the message or the signal to the network server after the tune away commences and before an acknowledgement message associated with the data transmission is sent from the mobile wireless apparatus to the network server.

14. The mobile wireless apparatus of claim 13, wherein the message or signal is transmitted before the tune away of the at least one air interface from the first wireless network to the second wireless network concludes.

15. The mobile wireless apparatus of claim 13, wherein the function implemented by the network server comprises the network server imposing a delay on invoking a timeout condition resulting from the network server not receiving one or more acknowledgement messages from the mobile wireless apparatus.

16. The mobile wireless apparatus of claim 13, wherein the function implemented by the network server comprises the network server adjusting the transmission of data to the mobile wireless apparatus for at least a period of time, such that acknowledgement messages from the mobile wireless apparatus are required less frequently.