Uplink congestion control based on SIP messaging

1. A method, comprising:

receiving session initiation protocol (SIP) messages from user equipment devices (UEs) via established wireless uplink connections;

monitoring a rate of the SIP messages received from the UEs;

identifying whether the rate of received SIP messages exceeds a first threshold during a first period of time;

generating predetermined time delays to randomly vary between different UEs and to shape a cumulative distribution of SIP messages resent by the UEs; and

sending SIP response messages to the UEs to reduce congestion on the wireless uplink connections upon identifying that the rate of received SIP messages exceeded the first threshold over the first period of time, wherein the sent SIP response messages instruct the UEs to resend the SIP messages after the predetermined time delays.

2. The method of claim 1 , wherein upon sending SIP response messages to the UEs to reduce congestion on the wireless uplink connections, the method further comprises:

identifying whether the rate of received SIP messages decreases below a second threshold during a second period of time; and

ceasing the sending of SIP response messages to reduce congestion on the wireless uplink connections upon identifying that the rate of received SIP messages decreased below the second threshold during the second period of time.

3. The method of claim 1 , wherein the receiving SIP messages from the UEs further comprises:

receiving registration request messages, invite messages, subscribe request messages, notification messages, or publish messages.

4. The method of claim 1 , wherein the predetermined time delays are based on a class of user.

5. The method of claim 1 , wherein sending SIP response messages further comprise:

sending at least one of a Not Found message, a Request Entity Too Large message, a Temporarily Unavailable message, a Busy Here message, a Server Internal Error message, a Service Unavailable message, or a Server Timed Out message.

6. The method of claim 1 , wherein the SIP response messages include provisional response codes.

7. The method of claim 2 , wherein the first threshold and second threshold include overload control activate rates associated with a base station.

8. A network device, comprising:

a network interface;

a memory configured to store instructions; and

a processor coupled to the network interface and the memory, wherein the processor is configured to execute the instructions stored in the memory to:

receive session initiation protocol (SIP) messages from user equipment devices (UEs) via established wireless uplink connections,

monitor a rate of the SIP messages received from the UEs,

identify whether the rate of received SIP messages exceeds a first threshold during a first period of time,

generate predetermined time delays to randomly vary between different UEs and to shape a cumulative distribution of SIP messages resent by the UEs, and

send SIP response messages to the UEs to reduce congestion on the wireless uplink connections upon identifying that the rate of received SIP messages exceeded the first threshold over the first period of time, wherein the sent SIP response messages instruct the UEs to resend the SIP messages after the predetermined time delays.

9. The network device of claim 8 , wherein upon the processor sending SIP response messages to the UEs to reduce congestion on the wireless uplink connections, the instructions further cause the processor to:

identify whether the rate of received SIP messages decreases below a second threshold during a second period of time, and

cease the sending of SIP response messages to reduce congestion on the wireless uplink connections upon determining that the rate of received SIP messages decreased below the second threshold during the second period of time.

10. The network device of claim 8 , wherein the instructions to receive SIP messages from the UEs further cause the processor to:

receive registration request messages, invite messages, subscribe request messages, notification messages, or publish messages.

11. The network device of claim 8 , wherein the predetermined time delays are based on a class of user.

12. The network device of claim 8 , wherein the instructions to send SIP response messages further cause the processor to:

send at least one of a Not Found message, a Request Entity Too Large message, a Temporarily Unavailable message, a Busy Here message, a Server Internal Error message, a Service Unavailable message, or a Server Timed Out message.

13. The network device of claim 8 , wherein the SIP response messages include provisional response codes.

14. The network device of claim 9 , wherein the first threshold and second threshold include overload control activate rates associated with a base station.

15. A non-transitory computer-readable medium comprising instructions, which, when executed by a processor, cause the processor to:

receive session initiation protocol (SIP) messages from user equipment devices (UEs) via established wireless uplink connections;

monitor a rate of the SIP messages received from the UEs;

identify whether the rate of received SIP messages exceeds a first threshold during a first period of time;

generate predetermined time delays to randomly vary between different UEs and to shape a cumulative distribution of SIP messages resent by the UEs; and

send SIP response messages to the UEs to reduce congestion on the wireless uplink connections upon identifying that the rate of received SIP messages exceeded the first threshold over the first period of time, wherein the sent SIP response messages instruct the UEs to resend the SIP messages after the predetermined time delays.

16. The non-transitory computer-readable medium of claim 15 , wherein upon sending SIP response messages to the UEs to reduce congestion on the wireless uplink connections, the instructions cause the processor to:

identify whether the rate of received SIP messages decreases below a second threshold during a second period of time; and

cease the sending of SIP response messages to reduce congestion on the wireless uplink connections upon determining that the rate of received SIP messages decreased below the second threshold during the second period of time.

17. The non-transitory computer-readable medium of claim 15 , wherein the instructions to receive SIP messages from the UEs further cause the processor to:

receive registration request messages, invite messages, subscribe request messages, notification messages, or publish messages.

18. The non-transitory computer-readable medium of claim 15 , wherein the predetermined time delays are based on a class of user.

19. The non-transitory computer-readable medium of claim 15 , wherein the SIP response messages include provisional response codes.

20. The non-transitory computer-readable medium of claim 16 , wherein the first threshold and second threshold include overload control activate rates associated with a base station.