# US 2025/0098017 A1 · Non-access stratum signaling > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0098017 A1 - Document ID: US20250098017A1 - Status: Published application - Kind: A1 - Application number: 18/888,232 - Filed: 2024-09-18 - Published: 2025-03-20 - Earliest claimed: 2023-09-18 - Assignees: Nokia Technologies Oy - Applicants: Nokia Technologies Oy - Inventors: Devaki CHANDRAMOULI; Ethiraj ALWAR; Janne Veikko KAASALAINEN; Dariusz PALKA - Web page: https://patentgrep.com/patent/US20250098017A1 ## CPC - H04W 76/25: Maintenance of established connections - H04W 28/0273: {adapting protocols for flow control or congestion control to wireless environment, e.g. adapting transmission control protocol [TCP] (wireless network protocols or protocol adaptations to wireless operation, e.g. wireless application protocol H04W80/00)} - H04W 76/11: Allocation or use of connection identifiers - H04W 76/12: Setup of transport tunnels - H04W 92/24: between backbone network devices - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Example embodiments of the present disclosure relate to methods, devices, apparatuses and computer readable storage medium for distributed non-access stratum (NAS). The method comprises: providing, to a second apparatus, a NAS message transport configuration indicating at least one of a mapping between NAS services and radio bearers or a mapping between NAS services and NAS service type identifiers; and routing an NAS message between the second apparatus and a third apparatus based at least on the NAS message transport configuration, wherein the third apparatus is determined from a plurality of apparatuses based on the NAS message transport configuration. ## Claims ### Claim at position 1 -29. (canceled) ### Claim 30 A first apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus at least to: provide, to a second apparatus, a non-access stratum (NAS) message transport configuration indicating a mapping between NAS services and radio bearers and a mapping between the NAS services and NAS service type identifiers, wherein the mapping between the NAS services and the radio bearers comprises the following: a mapping between the NAS services and respective dedicated signaling radio bearers (SRBs), and a mapping between the NAS services and respective dedicated data radio bearers (DRBs), wherein in a radio resource control (RRC) state, respective DRBs are mapped to corresponding F1-U tunnels, and wherein each of the corresponding F1-U tunnels is mapped to a NAS service wherein different priorities are associated to the SRBs and the DRBs; route an NAS message between the second apparatus and a third apparatus based at least on the NAS message transport configuration, wherein the third apparatus is determined from a plurality of apparatuses based on the NAS message transport configuration; in response to receiving a first downlink NAS message associated with a first NAS service from the third apparatus, determine, based on the NAS message transport configuration, a dedicated SRB corresponding to the first NAS service; transmit the first downlink NAS message to the second apparatus via the determined dedicated SRB; in response to receiving an uplink NAS message via a dedicated SRB from the second apparatus, determine a second NAS service corresponding to the dedicated SRB; transmit the uplink NAS message the third apparatus associated with the determined second NAS service; in response to receiving a second downlink NAS message associated with a third NAS service from the third apparatus, determine a F1-U tunnel corresponding to the third NAS service; transmit the second downlink NAS message to the second apparatus via a dedicated DRB corresponding to the determined F1-U tunnel; in response to receiving a second uplink NAS message via a dedicated DRB from the second apparatus, determine a F1-U tunnel corresponding to the dedicated SRB; and transmit the second uplink NAS message to the third apparatus associated with a fourth NAS service corresponding to the determined F1-U tunnel. ### Claim 31 (depends on 30) The first apparatus of claim 30, wherein the first apparatus is caused to: receive, from the second apparatus, an indication of one or more NAS services to be required by the second apparatus; and configure the at least one mapping based on the indication. ### Claim 32 (depends on 31) The first apparatus of claim 31, wherein the first apparatus is caused to: transmit, to the second apparatus, a request for the second apparatus to report the one or more NAS services to be required by the second apparatus. ### Claim 33 (depends on 32) The first apparatus of claim 32, wherein the first apparatus is caused to: in response to receiving a third uplink NAS message from the second apparatus, detect, from the third uplink NAS message, a NAS service type identifier of a NAS service; and transmit the third uplink NAS message to the third apparatus based on the NAS service type identifier. ### Claim 34 (depends on 33) The first apparatus of claim 33, wherein the first apparatus is caused to: route the third uplink NAS message between the second apparatus and the third apparatus based on a NAS data adaptation protocol (NDAP). ### Claim 35 (depends on 34) The first apparatus of claim 34, wherein a NAS packet of the third uplink NAS message comprises a NDAP header and a payload of the third uplink NAS message, wherein a NAS service type identifier corresponding to the NAS service of the third uplink NAS message is indicated in the NDAP header. ### Claim 36 (depends on 35) The first apparatus of claim 35, wherein the first apparatus is caused to: in response to receiving a NAS packet of the uplink NAS message, determine the NAS service type identifier corresponding to the NAS service of the uplink NAS message from the NDAP header of the NAS packet of the uplink NAS message; and route the uplink NAS message to the third apparatus or the second apparatus corresponding to the NAS service type identifier. ### Claim 37 (depends on 36) The first apparatus of claim 36, wherein the first apparatus comprises a radio access network device, the second apparatus comprises a NAS entity of a terminal device and the third apparatus comprises a NAS entity or a network function of a core network. ### Claim 38 A system comprising: a first apparatus; at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus at least to: provide, to a second apparatus, a non-access stratum (NAS) message transport configuration indicating a mapping between NAS services and radio bearers and a mapping between the NAS services and NAS service type identifiers, wherein the mapping between the NAS services and the radio bearers comprises the following: a mapping between the NAS services and respective dedicated signaling radio bearers (SRBs), and a mapping between the NAS services and respective dedicated data radio bearers (DRBs), wherein in a radio resource control (RRC) state, respective DRBs are mapped to corresponding F1-U tunnels, and wherein each of the corresponding F1-U tunnels is mapped to a NAS service wherein different priorities are associated to the SRBs and the DRBs; route an NAS message between the second apparatus and a third apparatus based at least on the NAS message transport configuration, wherein the third apparatus is determined from a plurality of apparatuses based on the NAS message transport configuration; in response to receiving a first downlink NAS message associated with a first NAS service from the third apparatus, determine, based on the NAS message transport configuration, a dedicated SRB corresponding to the first NAS service; transmit the first downlink NAS message to the second apparatus via the determined dedicated SRB; in response to receiving an uplink NAS message via a dedicated SRB from the second apparatus, determine a second NAS service corresponding to the dedicated SRB; transmit the uplink NAS message the third apparatus associated with the determined second NAS service; in response to receiving a second downlink NAS message associated with a third NAS service from the third apparatus, determine a F1-U tunnel corresponding to the third NAS service; transmit the second downlink NAS message to the second apparatus via a dedicated DRB corresponding to the determined F1-U tunnel; in response to receiving a second uplink NAS message via a dedicated DRB from the second apparatus, determine a F1-U tunnel corresponding to the dedicated SRB; and transmit the second uplink NAS message to the third apparatus associated with a fourth NAS service corresponding to the determined F1-U tunnel. ### Claim 39 (depends on 38) The system of claim 38, wherein the first apparatus is caused to: receive, from the second apparatus, an indication of one or more NAS services to be required by the second apparatus; and configure the at least one mapping based on the indication. ### Claim 40 (depends on 39) The system of claim 39, wherein the first apparatus is caused to: transmit, to the second apparatus, a request for the second apparatus to report the one or more NAS services to be required by the second apparatus. ### Claim 41 (depends on 40) The system of claim 40, wherein the first apparatus is caused to: in response to receiving a third uplink NAS message from the second apparatus, detect, from the third uplink NAS message, a NAS service type identifier of a NAS service; and transmit the third uplink NAS message to the third apparatus based on the NAS service type identifier. ### Claim 42 (depends on 41) The system of claim 41, wherein the first apparatus is caused to: route the third uplink NAS message between the second apparatus and the third apparatus based on a NAS data adaptation protocol (NDAP). ### Claim 43 (depends on 42) The system of claim 42, wherein a NAS packet of the third uplink NAS message comprises a NDAP header and a payload of the third uplink NAS message, wherein a NAS service type identifier corresponding to the NAS service of the third uplink NAS message is indicated in the NDAP header. ### Claim 44 (depends on 43) The system of claim 43, wherein the first apparatus is caused to: in response to receiving a NAS packet of the uplink NAS message, determine the NAS service type identifier corresponding to the NAS service of the uplink NAS message from the NDAP header of the NAS packet of the uplink NAS message; and route the uplink NAS message to the third apparatus or the second apparatus corresponding to the NAS service type identifier. ### Claim 45 (depends on 44) The system of claim 44, wherein the first apparatus comprises a radio access network device, the second apparatus comprises a NAS entity of a terminal device and the third apparatus comprises a NAS entity or a network function of a core network. ### Claim 46 A method comprising: providing, by a first apparatus to a second apparatus, a non-access stratum (NAS) message transport configuration indicating a mapping between NAS services and radio bearers and a mapping between the NAS services and NAS service type identifiers, wherein the mapping between the NAS services and the radio bearers comprises the following: a mapping between the NAS services and respective dedicated signaling radio bearers (SRBs), and a mapping between the NAS services and respective dedicated data radio bearers (DRBs), wherein in a radio resource control (RRC) state, respective DRBs are mapped to corresponding F1-U tunnels, and wherein each of the corresponding F1-U tunnels is mapped to a NAS service wherein different priorities are associated to the SRBs and the DRBs; routing, by the first apparatus, an NAS message between the second apparatus and a third apparatus based at least on the NAS message transport configuration, wherein the third apparatus is determined from a plurality of apparatuses based on the NAS message transport configuration; in response to receiving a first downlink NAS message associated with a first NAS service from the third apparatus, determining, by the first apparatus, based on the NAS message transport configuration, a dedicated SRB corresponding to the first NAS service; transmitting, by the first apparatus, the first downlink NAS message to the second apparatus via the determined dedicated SRB; in response to receiving an uplink NAS message via a dedicated SRB from the second apparatus, determining, by the first apparatus, a second NAS service corresponding to the dedicated SRB; transmitting, by the first apparatus, the uplink NAS message the third apparatus associated with the determined second NAS service; in response to receiving a second downlink NAS message associated with a third NAS service from the third apparatus, determining, by the first apparatus, a F1-U tunnel corresponding to the third NAS service; transmitting, by the first apparatus, the second downlink NAS message to the second apparatus via a dedicated DRB corresponding to the determined F1-U tunnel; in response to receiving a second uplink NAS message via a dedicated DRB from the second apparatus, determining, by the first apparatus, a F1-U tunnel corresponding to the dedicated SRB; and transmitting, by the first apparatus, the second uplink NAS message to the third apparatus associated with a fourth NAS service corresponding to the determined F1-U tunnel. ### Claim 47 (depends on 46) The method of claim 46, further comprising: receiving, by the first apparatus from the second apparatus, an indication of one or more NAS services to be required by the second apparatus; and configuring, by the first apparatus, the at least one mapping based on the indication. ### Claim 48 (depends on 47) The method of claim 47, further comprising: transmitting, by the first apparatus to the second apparatus, a request for the second apparatus to report the one or more NAS services to be required by the second apparatus. ### Claim 49 (depends on 48) The method of claim 48, further comprising: in response to receiving a third uplink NAS message from the second apparatus, detecting, by the first apparatus from the third uplink NAS message, a NAS service type identifier of a NAS service; transmitting, by the first apparatus, the third uplink NAS message to the third apparatus based on the NAS service type identifier; routing, by the first apparatus, the third uplink NAS message between the second apparatus and the third apparatus based on a NAS data adaptation protocol (NDAP), wherein a NAS packet of the third uplink NAS message comprises a NDAP header and a payload of the third uplink NAS message, wherein a NAS service type identifier corresponding to the NAS service of the third uplink NAS message is indicated in the NDAP header; in response to receiving a NAS packet of the uplink NAS message, determining, by the first apparatus, the NAS service type identifier corresponding to the NAS service of the uplink NAS message from the NDAP header of the NAS packet of the uplink NAS message; and routing, by the first apparatus, the uplink NAS message to the third apparatus or the second apparatus corresponding to the NAS service type identifier.