Poll scheduling for emergency calls

• US 20040151283A1
• Filed: 10/17/2003
• Published: 08/05/2004
• Est. Priority Date: 02/03/2003
• Status: Active Grant

• Current Assignee: Avaya Incorporated
• Original Assignee: Avaya Technology LLC (Avaya Incorporated)
• Inventors: Lazoff, David Michael
• Granted Patent: US 7,047,002 B2
• Time in Patent Office: Days
• US Class Current: 379/45
• CPC Class Codes: H04M 11/04 with alarm systems, e.g. fire, police or burglar alarm systems
• CPC Class Codes: H04M 2242/04 for emergency applications
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 74/085 collision avoidance
• CPC Class Codes: H04W 76/50 for emergency connections
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

An apparatus and methods for expeditious handling of emergency message frames (e.g., 911 voice-over-Internet-Protocol [VoIP] frames, etc.) sent by a station in a wireless local-area network are disclosed. The illustrative embodiment increases the probability with which an emergency message frame is accorded the highest quality-of-service by establishing polling schedules that preferentially accommodate stations that transmit emergency message frames.

Claims

1. A method comprising:

(a) receiving a polling request via a shared communications channel, wherein said polling request specifies a destination for a subsequent transmission via said shared communications channel; and

(b) determining whether to add the sender of said polling request to a polling schedule based on said destination.

2. The method of claim 1 wherein (b) is based on whether said destination is associated with an emergency call center.

3. The method of claim 1 wherein (b) is also based on a destination specified by a prior polling request, wherein the sender of said prior polling request is in said polling schedule.

4. The method of claim 1 further comprising

(c) determining whether to delete the sender of a prior polling request from said polling schedule based on the destination specified by said prior polling request.

5. The method of claim 4 further comprising:

(d) deleting the sender of said prior polling request from said polling schedule; and

(e) adding the sender of said polling request to said polling schedule;

when;

the destination specified by said polling request is associated with an emergency call center, and

the destination specified by said prior polling request is unassociated with any emergency call center.

6. A method comprising:

(a) receiving a polling request via a shared communications channel, wherein said polling request specifies a destination for a subsequent transmission via said shared communications channel; and

(b) determining a position in a polling schedule for the sender of said polling request based on said destination.

7. The method of claim 6 wherein (b) is based on whether said destination is associated with an emergency call center.

8. The method of claim 6 wherein (b) is also based on a destination specified by a prior polling request, wherein the sender of said prior polling request is in said polling schedule.

9. A method comprising:

(a) receiving a polling request via a shared communications channel, wherein said polling request specifies a destination for a subsequent transmission via said shared communications channel; and

(b) determining a transmission opportunity duration in a polling schedule for the sender of said polling request based on said destination.

10. The method of claim 9 wherein (b) is based on whether said destination is associated with an emergency call center.

11. The method of claim 9 wherein (b) is also based on a destination specified by a prior polling request, wherein the sender of said prior polling request is in said polling schedule.

12. The method of claim 9 further comprising:

(c) determining a position in said polling schedule for the sender of said polling request based on said destination.

13. A method comprising:

receiving via a shared-communications channel

(i) a first frame comprising a first source, a first destination, and a first payload, and

(ii) a second frame comprising a second source, a second destination, and a second payload; and

transmitting via said shared-communications channel

(iii) a third frame comprising a poll and said first payload, and

(iv) a fourth frame comprising a poll and said second payload

in an order based on said first source and said second source

when said first destination and said second destination are in a polling schedule.

14. The method of claim 13 wherein said order is based on whether said first source is associated with an emergency call center and on whether said second source is associated with an emergency call center.

15. The method of claim 13 wherein said order is also based on the positions of said first destination and said second destination in said polling schedule.

16. An apparatus comprising:

a receiver for receiving a polling request via a shared communications channel, wherein said polling request specifies a destination for a subsequent transmission via said shared communications channel; and

a processor for determining, based on said destination, at least one of;

whether to add the sender of said polling request to a polling schedule,

a position in said polling schedule for the sender of said polling request, and

a transmission opportunity duration for the sender of said polling request.

17. The apparatus of claim 16 wherein said processor'"'"'s determining is based on whether said destination is associated with an emergency call center.

18. The apparatus of claim 16 wherein said processor'"'"'s determining is also based on a destination specified by a prior polling request, wherein the sender of said prior polling request is in said polling schedule.

19. An apparatus comprising:

a memory for storing a polling schedule;

a receiver for receiving via a shared-communications channel

(i) a first frame comprising a first source, a first destination, and a first payload, and

(ii) a second frame comprising a second source, a second destination, and a second payload; and

a processor for;

generating a third frame comprising a poll and said first payload,

generating a fourth frame comprising a poll and said second payload, and

determining, based on said first source and said second source, an order in which to transmit said third frame and said fourth frame when said first destination and said second destination are in said polling schedule.

20. The apparatus of claim 19 wherein said order is based on whether said first source is associated with an emergency call center and on whether said second source is associated with an emergency call center.