Switching random access triggered by backoff
A method by a wireless device includes transmitting, to a network node, a first message to initiate a 2-step Random Access (RA) procedure to access a network. After transmitting the first message, the wireless device receives, from the network node, a second message including at least one parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure. Based on the parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure, the wireless device attempts to access the network using a 4-step RA procedure without waiting for the period of time.
1 . A A method by a wireless device, the method comprising:
transmitting, to a network node, a first message to initiate a 2-step Random Access, RA, procedure to access a network;
after transmitting the first message, receiving, from the network node, a second message, the second message comprising at least one parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure;
determining that the second message does not include an indication that the network received a RA preamble in the first message from the wireless device; and
based on the parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure and the second message not including the indication that the network node received a RA preamble in the first message, attempting to access the network using a 4-step RA procedure without waiting for the period of time.
2 . The method of claim 1 , wherein a maximum number of attempts for the 2-step RA procedure has not been exceeded when the attempt to access the network using the 4-step RA procedure is initiated.
3 . The method of claim 1 , wherein the second message comprises a msgB.
4 . The method of claim 1 , wherein the at least one parameter comprises a backoff indicator.
5 . The method of claim 1 , further comprising determining a RA occasion for performing the 4-step RA procedure.
6 . The method of claim 1 , further comprising determining that the second message indicates that the wireless device is to attempt to access the network using the 4-step RA procedure without waiting for the period of time.
7 . The method of claim 1 , further comprising determining that the wireless device is configured to ignore the at least one parameter.
8 . The method of claim 7 , wherein determining that the wireless device is configured to ignore the at least one parameter is based on at least one of:
a capability of the wireless device;
a property of data, an application, or a service that triggered the 2-step RA procedure;
whether the 2-step RA procedure is a prioritized random access procedure;
an RRC state of the wireless device;
a preamble group used for the transmission of the first message;
whether the network node configured the wireless device to ignore the at least one parameter; and
whether the wireless device is required to ignore the at least one parameter.
9 . A wireless device comprising:
processing circuitry configured to:
transmit, to a network node, a first message to initiate a 2-step Random Access, RA, procedure to access a network;
after transmitting the first message, receive, from the network node, a second message, the second message comprising at least one parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure;
determine that the second message does not include an indication that the network received a RA preamble in the first message from the wireless device; and
based on the parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure and the second message not including the indication that the network node received a RA preamble in the first message, attempt to access the network using a 4-step RA procedure without waiting for the period of time.
10 . The wireless device of claim 9 , wherein a maximum number of attempts for the 2-step RA procedure has not been exceeded when the attempt to access the network using the 4-step RA procedure is initiated.
11 . A method by a network node, the method comprising:
receiving, from a wireless device, a first message to initiate a 2-step Random Access, RA, procedure to access a network;
transmitting, to the wireless device, a second message, the second message comprising at least one parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure, wherein the second message does not include an indication that the network node received a RA preamble in the first message from the wireless device; and
before an expiration of the period of time that the wireless device is to wait, receiving a third message, from the wireless device, to initiate a 4-step RA procedure to access the network.
12 . The method of claim 11 , wherein a maximum number of attempts for the 2-step RA procedure has not been exceeded when the attempt to access the network using the 4-step RA procedure is initiated.
13 . The method of claim 11 , wherein the second message comprises a msgB.
14 . The method of claim 11 , wherein the at least one parameter comprises a backoff indicator.
15 . The method of claim 11 , further comprising configuring the wireless device to ignore the at least one parameter indicating that the wireless device is to wait the period of time before reattempting to access the network using the 2-step RA procedure when at least one condition is fulfilled.
16 . The method of claim 11 , wherein the second message indicates that the wireless device is to attempt to access the network using the 4-step RA procedure without waiting the period of time.
17 . The method of claim 11 , further comprising, prior to transmitting the second message to the wireless device, transmitting a configuration message to the wireless device to configure the wireless device to:
in response to receiving the second message, attempt to access the network using the 4-step RA procedure without waiting for the period of time.
18 . A network node comprising:
processing circuitry configured to:
receive, from a wireless device, a first message to initiate a 2-step Random Access, RA, procedure to access a network;
transmit, to the wireless device, a second message, the second message comprising at least one parameter indicating that the wireless device is to wait a period of time before reattempting to access the network using the 2-step RA procedure, wherein the second message does not include an indication that the network node received a RA preamble in the first message from the wireless device; and
before an expiration of the period of time that the wireless device is to wait, receive a third message, from the wireless device, to initiate a 4-step RA procedure to access the network.
19 . The network node of claim 18 , wherein a maximum number of attempts for the 2-step RA procedure has not been exceeded when the attempt to access the network using the 4-step RA procedure is initiated.