1. A server which receives data transmitted from a plurality of sensor nodes each having actions occurring intermittently, the server having an event-action controller that executes preset processing corresponding to each of the sensor nodes when the data transmitted by the corresponding sensor node satisfies a preset condition corresponding to the corresponding sensor node, wherein: the event-action controller has: an event-action table for storing event-action entries, each of the event-action entries respectively comprising a data ID assigned to the data transmitted by a corresponding sensor node of the plurality of sensor nodes, preset processing corresponding to the data ID, and a preset condition corresponding to the data ID, a cache for storing a subset of the event-action entries stored in the event-action table, a learning table for storing each data ID assigned to the data transmitted by the plurality of sensor nodes, a respective time for each data ID indicating when the server received a most recent data to which the data ID is assigned, and a respective estimated time of receiving a next data for each data ID subsequent to receiving the most recent data for the data ID calculated based on the respective time when the server received the most recent data to which the data ID is assigned, a forwarding controller for receiving each data ID stored in the learning table for which a balance of subtraction of a current time from the respective estimated time of receiving the next data for the data ID is shorter than a prescribed length of time from the learning table and forwarding the event-action entries of the event-action table that respectively comprise each data ID received from the learning table from the event-action table to the cache, and a cache access controller for determining whether or not the event-action entry respectively comprising the data ID for each data transmitted from any of the sensor nodes is stored in the cache.