A segment routing (SR) network has a plurality of interconnected SR gateways, where each of a plurality of local networks is connectable to an SR gateway at an edge router of the local network. An SR network control plane maintains a locator database that maps (i) a global IP (GIP) address for user equipment (UE) to (ii) an IP address of a downstream node associated with the UE along a path from the SR network to the UE. An SR gateway (i) receives a message for the UE and (ii) addresses the message to the IP address of the downstream node. The SR network control plane updates the locator database to map (i) the GIP address for the UE to (ii) a different IP address of a downstream node upon the SR network control plane determining that the association of the UE has changed to the different IP address.