A method for establishing a channel, comprising: receiving, by a first web real-time communication, WEBRTC, signaling gateway device, a session request message transmitted by a calling terminal, wherein the session request message comprises an identifier of a called terminal, and wherein the calling terminal is a WEBRTC terminal; transmitting, by the first WEBRTC signaling gateway device, a query request message comprising the identifier of the called terminal to a WEBRTC server, and receiving, by the first WEBRTC signaling gateway device, an access mode in which the called terminal accesses a WEBRTC signaling gateway device and a gateway identifier of the WEBRTC signaling gateway device accessed by the called terminal, wherein the access mode and the gateway identifier are transmitted by the WEBRTC server in response to the query request message, and wherein the access mode comprises accessing via WEB; determining, by the first WEBRTC signaling gateway device, that the called terminal is a WEBRTC terminal according to the access mode, and transmitting, by the first WEBRTC signaling gateway device, the session request message to the called terminal via the WEBRTC signaling gateway device corresponding to the gateway identifier; and receiving, by the first WEBRTC signaling gateway device, a session response message transmitted by the called terminal, and transmitting, by the first WEBRTC signaling gateway device, the session response message to the calling terminal, to enable the calling terminal to establish an end-to-end media channel between the calling terminal and the called terminal according to the session response message. receiving, by a first web real-time communication, WEBRTC, signaling gateway device, a session request message transmitted by a calling terminal, wherein the session request message comprises an identifier of a called terminal, and wherein the calling terminal is a WEBRTC terminal; transmitting, by the first WEBRTC signaling gateway device, a query request message comprising the identifier of the called terminal to a WEBRTC server, and receiving, by the first WEBRTC signaling gateway device, an access mode in which the called terminal accesses a WEBRTC signaling gateway device and a gateway identifier of the WEBRTC signaling gateway device accessed by the called terminal, wherein the access mode and the gateway identifier are transmitted by the WEBRTC server in response to the query request message, and wherein the access mode comprises accessing via WEB; determining, by the first WEBRTC signaling gateway device, that the called terminal is a WEBRTC terminal according to the access mode, and transmitting, by the first WEBRTC signaling gateway device, the session request message to the called terminal via the WEBRTC signaling gateway device corresponding to the gateway identifier; and receiving, by the first WEBRTC signaling gateway device, a session response message transmitted by the called terminal, and transmitting, by the first WEBRTC signaling gateway device, the session response message to the calling terminal, to enable the calling terminal to establish an end-to-end media channel between the calling terminal and the called terminal according to the session response message.