According to one aspect of the present disclosure, there is provided a method, by a virtual network function, that includes: receiving a first request from a user equipment (UE), the first request including first parameters and a first token, the first token being a vector value corresponding to a session state for the UE; determining the session state for the UE according to the first token; programming network resources according to the session state, the programming updating states of the network resources, wherein the session state for the UE is updated when the states of the network resources are updated; producing a second token corresponding to the updated session state for the UE; storing the updated session state and the second token; and transmitting the second token to the UE.