A communications system, comprising a centralized redirector, a plurality of resource servers (120a-120d), and a client (130a-130d), wherein the centralized redirector stores mapping information, and the mapping information is used to indicate a mapping relationship between a resource identifier and an identifier of a resource server in which resource information corresponding to the resource identifier is located; the client is configured to send a first request packet to a first resource server in the plurality of resource servers, wherein the first request packet comprises a first resource identifier, and the first request packet is used to request resource information corresponding to the first resource identifier; the first resource server is configured to send a second request packet to the centralized redirector when the resource information corresponding to the first resource identifier is not stored in the first resource server, wherein the second request packet comprises the first resource identifier; the centralized redirector is configured to send a second response packet to the first resource server based on the first resource identifier and the mapping information, wherein the second response packet is used to indicate a second resource server in which the resource information corresponding to the first resource identifier is located, wherein the centralized redirector is configured to obtain, based on the mapping information, an identifier of the second resource server that is in a mapping relationship with the first resource identifier; and send the second response packet to the first resource server, wherein the second response packet comprises the identifier of the second resource server; the first resource server is further configured to: obtain, from the second resource server, the resource information corresponding to the first resource identifier; and send a first response packet to the client, wherein the first response packet comprises the resource information corresponding to the first resource identifier; and wherein in the aspect of obtaining, from the second resource server, the resource information corresponding to the first resource identifier, the first resource server is configured to send a third request packet to the second resource server based on the identifier of the second resource server, wherein the third request packet comprises the first resource identifier; the second resource server is configured to send a third response packet to the first resource server, wherein the third response packet comprises the resource information corresponding to the first resource identifier; and the first resource server is configured to obtain, based on the third response packet, the resource information corresponding to the first resource identifier. the client is configured to send a first request packet to a first resource server in the plurality of resource servers, wherein the first request packet comprises a first resource identifier, and the first request packet is used to request resource information corresponding to the first resource identifier; the first resource server is configured to send a second request packet to the centralized redirector when the resource information corresponding to the first resource identifier is not stored in the first resource server, wherein the second request packet comprises the first resource identifier; the centralized redirector is configured to send a second response packet to the first resource server based on the first resource identifier and the mapping information, wherein the second response packet is used to indicate a second resource server in which the resource information corresponding to the first resource identifier is located, wherein the centralized redirector is configured to obtain, based on the mapping information, an identifier of the second resource server that is in a mapping relationship with the first resource identifier; and send the second response packet to the first resource server, wherein the second response packet comprises the identifier of the second resource server; the first resource server is further configured to: obtain, from the second resource server, the resource information corresponding to the first resource identifier; and send a first response packet to the client, wherein the first response packet comprises the resource information corresponding to the first resource identifier; and wherein in the aspect of obtaining, from the second resource server, the resource information corresponding to the first resource identifier, the first resource server is configured to send a third request packet to the second resource server based on the identifier of the second resource server, wherein the third request packet comprises the first resource identifier; the second resource server is configured to send a third response packet to the first resource server, wherein the third response packet comprises the resource information corresponding to the first resource identifier; and the first resource server is configured to obtain, based on the third response packet, the resource information corresponding to the first resource identifier.