Radio access fallback for internet protocol multimedia subsystem registration
The present application relates to devices and components including apparatus, systems, and methods for IMS registration in wireless networks.
1 . One or more non-transitory, computer-readable media having instructions that, when executed, cause processor circuitry to:
determine new radio (NR) access is blocked based on an Internet protocol multimedia subsystem (IMS) registration over NR failure;
detect a set of conditions, wherein the set of conditions includes: a determination that IMS registration over Long Term Evolution (LTE) is successful; and at least one additional condition that includes: a determination that a value of a retry counter is zero; a determination that a value of a retry counter is greater than zero and less than a maximum value and an LTE cell has changed; or a determination that a value of a retry counter is greater than zero and less than a maximum value, an LTE cell has not changed, and a blocking timer has expired; and
retry IMS registration over NR based on said determination that NR access is blocked based on the IMS registration over NR failure and detection of the set of conditions.
2 . The one or more non-transitory, computer-readable media of claim 1 , wherein the instructions, when executed, further cause the processor circuitry to:
start a blocking timer based on said determination that NR access is blocked based on the IMS registration over NR failure; and
detect an expiration of the blocking timer as a condition of the set of conditions.
3 . The one or more non-transitory, computer-readable media of claim 1 , wherein the at least one additional condition includes a determination that a value of a retry counter is greater than zero and less than a maximum value, an LTE cell has not changed, and a blocking timer has expired, wherein the retry counter is to track a number of times retries of the IMS registration over NR is unsuccessful.
4 . The one or more non-transitory, computer-readable media of claim 3 , wherein the at least one additional condition includes a determination that a retry counter is equal to zero, wherein the retry counter is to track a number of times retries of the IMS registration over NR is unsuccessful.
5 . The one or more non-transitory, computer-readable media of claim 3 , wherein the at least one additional condition includes a determination that a retry counter is greater than zero and less than a maximum value and an LTE cell has changed, wherein the retry counter is to track a number of times retries of the IMS registration over NR is unsuccessful.
6 . A method comprising:
determining access to a first radio access technology (RAT) is blocked based on an Internet protocol multimedia subsystem (IMS) registration over the first RAT failure;
detecting a set of conditions, wherein the set of conditions includes: a determination that IMS registration over a second RAT is successful; and at least one additional condition that includes: a determination that a value of a retry counter is zero; a determination that a value of a retry counter is greater than zero and less than a maximum value and a cell of the second RAT has changed; or a determination that a value of a retry counter is greater than zero and less than a maximum value, a cell of the second RAT has not changed, and a blocking timer has expired; and
retrying IMS registration over the first RAT based on said determining that access to the first RAT is blocked based on the IMS registration over the first RAT failure and said detecting the set of conditions.
7 . The method of claim 6 , further comprising:
starting a blocking timer based on said determining that access to the first RAT is blocked based on the IMS registration over the first RAT failure; and
detecting an expiration of the blocking timer as a condition of the set of conditions.
8 . The method of claim 6 , wherein the at least one additional condition includes a determination that a value of a retry counter is greater than zero and less than a maximum value, a cell of the second RAT has not changed, and a blocking timer has expired, wherein the retry counter is to track a number of times retries of the IMS registration over NR is unsuccessful.
9 . The method of claim 8 , wherein detecting the at least one additional condition includes a determination that a retry counter is equal to zero, wherein the retry counter to track a number of times retries of the IMS registration over the first RAT is unsuccessful.
10 . The method of claim 8 , wherein the at least one additional condition includes a determination that a retry counter is greater than zero and less than a maximum value and a cell of the second RAT has changed, wherein the retry counter tracks a number of times retries of the IMS registration over the first RAT is unsuccessful.
11 . A method comprising:
determining an Internet protocol multimedia subsystem (IMS) registration over New Radio (NR) is not successful for a predetermined period of time;
initiating an NR release based on said determining;
successfully performing an IMS registration over Long Term Evolution (LTE) based on said determining the IMS registration over NR is not successful for a predetermined period of time;
detecting, based on successfully performing the IMS over LTE, one or more conditions that includes: a determination that a value of a retry counter is zero; a determination that a value of a retry counter is greater than zero and less than a maximum value and an LTE cell has changed; or a determination that a value of a retry counter is greater than zero and less than a maximum value, an LTE cell has not changed, and a blocking timer has expired; and
retrying IMS registration over NR based on said detecting the one or more conditions.
12 . The method of claim 11 , wherein the predetermined period of time is 30 seconds.
13 . The method of claim 11 , further comprising:
blocking NR access based on said successfully performing the IMS registration over LTE.
14 . The method of claim 13 , wherein the one or more conditions includes a determination that a value of a retry counter is equal to zero, the retry counter to track a number of times retries of an IMS registration over NR is unsuccessful.
15 . The method of claim 14 , further comprising:
determining retrying IMS registration over NR is unsuccessful; and
based on said determining the retrying IMS registration over NR is unsuccessful, incrementing the retry counter and blocking NR access.
16 . The method of claim 15 , wherein retrying IMS registration over NR includes performing an LTE-to-NR reselection and the method further comprises:
attempting an IMS registration over LTE based on said determining the retrying IMS registration over NR is unsuccessful.
17 . The method of claim 13 , wherein the one or more conditions includes a determination that a value of a retry counter is greater than zero and less than a maximum number of retry attempts and an LTE cell has changed, the retry counter to track a number of times retries of an IMS registration over NR is unsuccessful.
18 . The method of claim 17 , wherein the maximum number is three.
19 . The method of claim 13 , wherein the one or more conditions includes a determination that a retry counter is greater than zero and less than a maximum number of retry attempts, an LTE cell has not changed, and a blocking timer has expired, the retry counter to track a number of times retries of an IMS registration over NR is unsuccessful and the blocking timer started or restarted after said blocking NR access.
20 . The method of claim 19 , further comprising:
setting a value of the blocking timer to twelve minutes.