A method for transmitting a data resource acquisition request, the method is used in a back-to-source processing inside a content delivery network, CDN, service cluster, the method comprising: when transmitting an acquisition request for a first data resource, obtaining, by a first node, traffic scheduling policies of a plurality of secondary nodes associated with a resource server to which the first data resource belongs, wherein the traffic scheduling policies are already locally-stored on the first node, and wherein the traffic scheduling policies are generated by each of the plurality of secondary nodes based on a local traffic load status; wherein the first node is an edge node or a dynamic parent node which has secondary nodes; selecting, by the first node, a target node among the plurality of secondary nodes based on the traffic scheduling policies of the plurality of secondary nodes; and transmitting, by the first node, the acquisition request for the first data resource to the target node; wherein the traffic scheduling policy is categorized into full traffic-split, partial traffic-split, and no traffic-split; periodically sending, by the first node, a probe request to each of the plurality of secondary nodes; receiving, by the first node, a probe response fed back by each of the plurality of secondary nodes, and determining, by the first node, a network delay between the first node and each of the plurality of secondary nodes; and determining, by the first node, a priority of each of the plurality of secondary nodes based on the network delay, wherein the smaller the network delay, the higher the priority of a secondary node; selecting, by the first node, the target node among the plurality of secondary nodes based on the traffic scheduling policies of the plurality of secondary nodes includes: sequentially selecting, by the first node, a candidate node among the plurality of secondary nodes in a descending order of the priority; and when a traffic scheduling policy of the candidate node is partial traffic-split and the acquisition request for the first data resource does not satisfy a preset criteria for traffic splitting, or when the traffic scheduling policy of the candidate node is no traffic-split, determining, by the first node, that the candidate node is the target node. when transmitting an acquisition request for a first data resource, obtaining, by a first node, traffic scheduling policies of a plurality of secondary nodes associated with a resource server to which the first data resource belongs, wherein the traffic scheduling policies are already locally-stored on the first node, and wherein the traffic scheduling policies are generated by each of the plurality of secondary nodes based on a local traffic load status; wherein the first node is an edge node or a dynamic parent node which has secondary nodes; selecting, by the first node, a target node among the plurality of secondary nodes based on the traffic scheduling policies of the plurality of secondary nodes; and transmitting, by the first node, the acquisition request for the first data resource to the target node; wherein the traffic scheduling policy is categorized into full traffic-split, partial traffic-split, and no traffic-split; periodically sending, by the first node, a probe request to each of the plurality of secondary nodes; receiving, by the first node, a probe response fed back by each of the plurality of secondary nodes, and determining, by the first node, a network delay between the first node and each of the plurality of secondary nodes; and determining, by the first node, a priority of each of the plurality of secondary nodes based on the network delay, wherein the smaller the network delay, the higher the priority of a secondary node; selecting, by the first node, the target node among the plurality of secondary nodes based on the traffic scheduling policies of the plurality of secondary nodes includes: sequentially selecting, by the first node, a candidate node among the plurality of secondary nodes in a descending order of the priority; and when a traffic scheduling policy of the candidate node is partial traffic-split and the acquisition request for the first data resource does not satisfy a preset criteria for traffic splitting, or when the traffic scheduling policy of the candidate node is no traffic-split, determining, by the first node, that the candidate node is the target node. sequentially selecting, by the first node, a candidate node among the plurality of secondary nodes in a descending order of the priority; and when a traffic scheduling policy of the candidate node is partial traffic-split and the acquisition request for the first data resource does not satisfy a preset criteria for traffic splitting, or when the traffic scheduling policy of the candidate node is no traffic-split, determining, by the first node, that the candidate node is the target node.