US 12,261,915 B2
Restoration of a PDN connection at PGW failure
Yong Yang, Kållered (SE)
Assigned to Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
Filed on Nov. 16, 2023, as Appl. No. 18/511,182.
Application 18/511,182 is a continuation of application No. 18/026,844, granted, now 11,870,854, previously published as PCT/EP2021/075757, filed on Sep. 20, 2021.
Claims priority of provisional application 63/081,066, filed on Sep. 21, 2020.
Prior Publication US 2024/0098148 A1, Mar. 21, 2024
Int. Cl. H04L 67/141 (2022.01); H04L 61/4511 (2022.01)
CPC H04L 67/141 (2013.01) [H04L 61/4511 (2022.05)] 11 Claims
OG exemplary drawing
 
1. A method of operation of a Mobility and Management Entity, MME, for a cellular communications system, the method comprising:
receiving an attach request from a User Equipment, UE;
sending a location update request to a Home Subscriber Station, HSS;
receiving a location update acknowledgement from the HSS;
sending a Domain Name Server, DNS, query request to a DNS, the DNS query comprising an Access Point Name, APN, Fully Qualified Domain Name, FQDN;
receiving a DNS query response from the DNS, the DNS query response comprising information that:
identifies a plurality of candidate combined Session Management Function and Packet Gateway Control Plane, SMF/PGW-C, instances that satisfy the DNS query request; and
identifies at least two candidate combined SMF/PGW-C instances that belong to a same SMF/PGW-C set, the at least two combined SMF/PGW-C instances comprising a first combined SMF/PGW-C instance and a second combined SMF/PGW-C instance;
selecting the first combined SMF/PGW-C instance;
sending, to a Serving Gateway, SGW, a first create session request that comprises information that indicates the first combined SMF/PGW-C instance;
receiving a first create session response from the SGW; and
sending an attach accept to the UE.