Access Availability of Multiaccess Packet Data Unit Session

1 . A method comprising:

receiving, by a wireless device from a network node, an access availability report indication for a multi-access packet data unit (MA-PDU) session; and

sending, by the wireless device to a user plane function, based on the access availability report indication, an access report message indicating:

an availability for a first access of the MA-PDU session;

a first access type associated with the first access of the MA-PDU session; and

a first radio access technology type associated with the first access type.

2 . The method of claim 1 , wherein the receiving the access availability report indication comprises receiving a measurement assistance information parameter comprising the access availability report indication.

3 . The method of claim 2 , wherein the receiving the access availability report indication comprises receiving a packet data unit session establishment accept message comprising the measurement assistance information parameter.

4 . The method of claim 2 , wherein the receiving the measurement assistance information parameter comprises receiving a non-access stratum message, a protocol configuration option, and/or an extended protocol configuration options comprising the measurement assistance information parameter.

5 . The method of claim 1 , wherein the receiving the access availability report indication comprises receiving a packet data unit session establishment accept message comprising the access availability report indication.

6 . The method of claim 1 , wherein the MA-PDU session is a packet data unit session associated with the first access and a second access, the second access having a same access type as the first access and a different radio access technology type from the first access.

7 . The method of claim 1 , wherein the access report message is a performance measurement function protocol (PMFP) access report message.

8 . The method of claim 1 , wherein the first access of the MA-PDU session is at least one of:

an MA-PDU session leg associated with the first access type and the first radio access technology type associated with the first access type; or

a child session associated with the first access type and the first radio access technology type associated with the first access type.

9 . The method of claim 8 , wherein the MA-PDU session is a packet data unit session associated with the first access and a second access, the second access having a same access type as the first access and a different radio access technology type from the first access, and wherein the sending the access report message comprises sending the access report message via the second access of the MA-PDU session.

10 . The method of claim 1 , wherein the availability is that the first access of the MA-PDU session is available or that the first access of the MA-PDU session is unavailable.

11 . The method of claim 1 , wherein the access report message indicates that the first access of the MA-PDU session is available based on at least one of:

successful radio link failure recovery procedure associated with the first access, the first access type and/or the first radio access technology type;

the wireless device being within a coverage area of the first access; or

the wireless device transitioning to and/or being in a connected mode over the first access.

12 . The method of claim 1 , wherein the access report message indicates that the first access of the MA-PDU session is unavailable based on at least one of:

a radio link failure for a connection of the wireless device with a first radio access network associated with the first access, the first access type and/or the first radio access technology type;

the wireless device being out of a coverage area of the first access; or

the wireless device transitioning to and/or being in an idle mode and/or inactive mode over the first access.

13 . The method of claim 1 , further comprising sending, by the wireless device to the network node, a request to establish the MA-PDU session.

14 . The method of claim 13 , wherein the sending the request to establish the MA-PDU session comprises sending a non-access stratum message comprising the request to establish the MA-PDU session.

15 . The method of claim 1 , further comprising receiving, by the wireless device from the network node, a message indicating an activation or deactivation of the first access.

16 . The method of claim 15 , wherein the receiving the message indicating the activation or deactivation of the first access is via an access network of the first radio access technology type.

17 . The method of claim 1 , wherein the network node is a session management function.

18 . A wireless device, comprising:

one or more processors; and

memory storing instructions that, when executed by the one or more processors, cause the wireless device to perform:

receiving, from a network node, an access availability report indication for a multi-access packet data unit (MA-PDU) session; and

sending, to a user plane function, based on the access availability report indication, an access report message indicating:

an availability for a first access of the MA-PDU session;

a first access type associated with the first access of the MA-PDU session; and

a first radio access technology type associated with the first access type.

19 . The wireless device of claim 18 , wherein the instructions, when executed by the one or more processors, further cause the wireless device to perform sending, to the network node, a request to establish the MA-PDU session.

20 . A method comprising:

receiving, by a user plane function from a wireless device, based on an access availability report indication for a multi-access packet data unit (MA-PDU) session, an access report message indicating:

an availability for a first access of the MA-PDU session;

a first access type associated with the first access of the MA-PDU session; and

a first radio access technology type associated with the first access type.