METHOD AND APPARATUS FOR SERVING GATEWAY USER PLANE AND INTERMEDIATE USER PLANE SELECTION BASED ON APN/DNN AND ROAMING STATUS OF THE SUBSCRIBER
A System and method for selecting a Serving Gateway User Plane/Intermediate User Plane Function/User Plane Function (SGW-U/I-UPF/UPF) for a mobile device in a visited network node where a roaming or a non-roaming status for the mobile device is determined, an Access Point Name (APN)/Data Network Name (DNN) for the mobile device is determined, where a Serving Gateway Control Plane/Session Management Function (SGW-C/SMF) node selects a first SGW-U/I-UPF/UPF or a second SGW-U/I-UPF/UPF for the mobile device based on the determination of the mobile device being in a roaming or a non-roaming status.
1 . A method for selecting a Serving Gateway User Plane/Intermediate User Plane Function/User Plane Function (SGW-U/I-UPF/UPF) for a mobile device in a visited network node comprising the steps of:
connecting the mobile device to a visited network node;
determining a roaming or a non-roaming status for the mobile device;
determining an Access Point Name (APN)/Data Network Name (DNN) for the mobile device;
providing a Serving Gateway Control Plane/Session Management Function (SGW-C/SMF) node adapted to select a first SGW-U/I-UPF/UPF or a second SGW-U/I-UPF/UPF for the mobile device, wherein the first SGW-U/I-UPF/UPF is different from the second SGW-U/I-UPF/UPF; and
selecting either the first SGW-U/I-UPF/UPF or the second SGW-U/I-UPF/UPF based on a determination of the mobile device being in a roaming or a non-roaming status, respectively.
2 . The method according to claim 1 , wherein the step of selecting either the first SGW-U/I-UPF/UPF or the second SGW-U/I-UPF/UPF based on a determination of the mobile device being in a roaming or a non-roaming status respectively further comprises, selecting the first SGW-U/I-UPF/UPF or the second SGW-U/I-UPF/UPF based on the APN/DNN for the mobile device.
3 . The method according to claim 2 , wherein the visited network node comprises an evolved NodeB (eNB) that is connected to a Mobility Management Entity (MME), which is in turn connected to a Serving Gateway Control Plane (SGW-C).
4 . The method according to claim 3 , further comprising the steps of:
connecting the SGW-C to a Serving Gateway User Plane (SGW-U) for voice, and
connecting the SGW-C to a SGW-U for data.
5 . The method according to claim 4 , wherein the SGW-C is further connected to a Public Data Network (PDN) Gateway Control plane (PGW-C), the method further comprising the steps of:
connecting the SGW-U for voice to a PDN Gateway User plane (PGW-C) for voice; and
connecting the SGW-U for data to a PGW-C for data.
6 . The method according to claim 2 , wherein the visited network node comprises a next generation NodeB (gNB) that is connected to an Access and Mobility Management Function (AMF).
7 . The method according to claim 6 , wherein the AMF is further connected to a Session Management Function (SMF).
8 . The method according to claim 7 , further comprising the steps of:
connecting the SMF to an Intermediate User Plane Function (I-UPF) for voice, and
connecting the SMF to an I-UPF for data.
9 . The method according to claim 8 , wherein the SMF is further connected to a UPF Packet Data Unit Session Anchor (UPF-PSA) for voice and an UPF-PSA for data, the method further comprising the steps of:
connecting the I-UPF for voice to the UPF-PSA for voice; and
connecting the I-UPF for data to the UPF-PSA for data.
10 . The method according to claim 8 , wherein the SMF comprises a Visited SMF (V-SMF).
11 . The method according to claim 10 , wherein the V-SMF is further connected to a Home SMF (H-SMF), the method further comprising the steps of:
connecting the H-SMF to a UPF Packet Data Unit Session Anchor (UPF-PSA) for voice; and
connecting the H-SMF to a UPF-PSA for data.
12 . The method according to claim 2 , wherein the SGW-C determines roaming status of a subscriber as follows:
the SGW-C compares a Public Land Mobile Network ID (PLMNID) derived from both an Access Point Name (APN) and an International Mobile Subscriber Identity (IMSI) with a configured list of PLMN-IDs on the SGW-C, wherein,
if both derived PLMN-IDs are the same and match with an entry in the configured list, the roaming status of the subscriber is considered as Home on the SGW-C,
if both derived PLMN-IDs are the same but do not match with an entry in the configured list, the roaming status of the subscriber is considered as Roaming on the SGW-C, or
if both derived PLMN-IDs are different, and the APN PLMN-ID matches with an entry in the configured list, the roaming status of the subscriber is considered as Visited on the SGW-C.
13 . The method according to claim 12 , wherein the SMF in a Visited network determines a roaming status of the subscriber as follows:
the SMF compares the PLMNID derived from both Data Network Name (DNN) and Subscription Permanent Identifier (SUPI) with a configured list of PLMN-IDs on the SMF, wherein,
if both derived PLMN-IDs are the same and matches with an entry in the configured list of PLMN-IDs on the SMF, the roaming status of the subscriber is considered as Home on the SMF,
if both derived PLMN-IDs are the same but do not match with an entry in the configured list of PLMN-IDs on SMF, the roaming status of the subscriber is considered as Roaming on the SMF, or
if both derived PLMN-IDs are different, and the DNN PLMN-ID matches with an entry in the configured list of PLMN-IDs on SMF, the roaming status of the subscriber is considered as Visited on the SMF.