A multicast implementation method, comprising: sending, by a live service server, a multicast resource allocation request to a multicast resource management server, wherein the multicast resource allocation request comprises a channel identifier; receiving, by the live service server, a multicast resource allocation response sent by the multicast resource management server, wherein the multicast resource allocation response comprises a correspondence between the channel identifier and the multicast IP address; sending, by the live service server, a live stream injection request to the multicast resource management server, wherein the live stream injection request is used to instruct the multicast resource management server to allocate a live stream injection node configured to inject a live stream into a network for the live stream to be transmitted in the network; receiving, by the live service server, a live stream injection response sent by the multicast resource management server, wherein the live stream injection response comprises a live stream injection node address; sending, by the live service server, a live stream injection instruction to a live stream injection node according to the live stream injection node address, wherein the live stream injection instruction carries a multicast IP address and authentication information, so that the live stream injection node returns response information after authentication succeeds; receiving, by the live service server, a stream pushing address sent by the live stream injection node; and instructing, by the live service server, a live content source to send a live stream to the live stream injection node according to the stream pushing address, so that the live stream injection node corresponding to the stream pushing address multicasts the live stream by using the multicast IP address, wherein the sending, by the live service server, a multicast resource allocation request to the multicast resource management server comprises: sending, by the live service server, the multicast resource allocation request to the multicast resource management server when a quantity of target clients is greater than a first threshold, wherein the target client is a client that has joined, by using the multicast IP address, a multicast channel corresponding to the channel identifier. sending, by a live service server, a multicast resource allocation request to a multicast resource management server, wherein the multicast resource allocation request comprises a channel identifier; receiving, by the live service server, a multicast resource allocation response sent by the multicast resource management server, wherein the multicast resource allocation response comprises a correspondence between the channel identifier and the multicast IP address; sending, by the live service server, a live stream injection request to the multicast resource management server, wherein the live stream injection request is used to instruct the multicast resource management server to allocate a live stream injection node configured to inject a live stream into a network for the live stream to be transmitted in the network; receiving, by the live service server, a live stream injection response sent by the multicast resource management server, wherein the live stream injection response comprises a live stream injection node address; sending, by the live service server, a live stream injection instruction to a live stream injection node according to the live stream injection node address, wherein the live stream injection instruction carries a multicast IP address and authentication information, so that the live stream injection node returns response information after authentication succeeds; receiving, by the live service server, a stream pushing address sent by the live stream injection node; and instructing, by the live service server, a live content source to send a live stream to the live stream injection node according to the stream pushing address, so that the live stream injection node corresponding to the stream pushing address multicasts the live stream by using the multicast IP address, wherein the sending, by the live service server, a multicast resource allocation request to the multicast resource management server comprises: sending, by the live service server, the multicast resource allocation request to the multicast resource management server when a quantity of target clients is greater than a first threshold, wherein the target client is a client that has joined, by using the multicast IP address, a multicast channel corresponding to the channel identifier.