A communication system for converging different access technologies, comprising: a convergence terminal, a first access network and a convergence core network, wherein the convergence core network comprises a first convergence access switch, a traffic server and a Home Subscriber Server, HSS, wherein the convergence terminal is configured to access a network converging different access technologies, and to transmit a traffic request message including a traffic identifier to the first convergence access switch via the first access network when the convergence terminal is required to perform traffic; wherein the network includes the first access network and the convergence core network; the first convergence access switch is configured to acquire an address of the traffic server after the traffic request message including the traffic identifier is received, and to forward the traffic request message including the traffic identifier to the traffic server; the traffic server is configured to perform information interaction with the HSS after the traffic request message forwarded by the first convergence access switch is received, and to provide traffic to the convergence terminal through the network converging different access technologies when it is determined that the traffic server is able to provide the traffic to the convergence terminal; and the HSS is configured to perform information interaction with the traffic server and to determine whether the traffic server is able to provide the traffic to the convergence terminal; wherein the traffic server is further configured to, after the traffic server receives the traffic request message, determines that the traffic server is able to provide the traffic to the convergence terminal according to the resource of the traffic server, establish a traffic instance, acquire an address of an HSS corresponding to the convergence terminal according to a user number corresponding to the convergence terminal, and transmit a message requesting audit of the traffic to the HSS; the HSS is further configured to match a user number and traffic identifier in the received traffic audit message with user information saved in the HSS, and return the traffic server a response message indicating pass of the audit of the traffic when the matching succeeds; the system further comprising a second access network, wherein the convergence core network further comprises a second convergence access switch, wherein the convergence terminal is further configured to, when a cell handover is necessary, transmit a handover request to the first access network; wherein the handover request includes a location identifier of a target cell; wherein the location identifier includes: a cell identifier, an identifier of a second access network and an identifier of a second convergence access switch; implement a handover by cooperating with the second access network after receiving a handover implementation message from the first access network; wherein the convergence terminal is configured, when the handover is performed, to establish a control channel with the second access network; and transmit a handover success message to the second access network after the handover is completed; the first access network is further configured to convert format of the handover request, forward the converted handover request to the first convergence access switch after receiving the handover request from the convergence terminal; notify the convergence terminal to implement the handover after receiving the handover implementation message from the first convergence access switch; and remove all channels between them by cooperating with the convergence terminal after receiving a notification of handover completion forwarded by the first convergence access switch; the first convergence access switch is further configured to forward the converted handover request to the second convergence access switch after receiving the converted handover request forwarded by the first access network; and notify the first access network to implement the handover after receiving the notification of handover implementation from the second convergence access switch; forward the notification of handover completion to the first access network after receiving the notification of handover completion from the first convergence access switch; the second convergence access switch is further configured to determine the second access network and forward the converted handover request to the second access network after receiving the converted handover request forwarded by the first convergence access switch; transmit the handover implementation message to the first convergence access switch to notify that the handover can be implemented; report the access location information of the convergence terminal to the HSS after receiving the handover success message from the second access network; notify the first convergence access switch that the handover is completed after receiving a location update response message from the HSS; the second access network is further configured to forward the handover success message to the second convergence access switch afte receiving the handover success message from the convergence terminal; and the HSS is further configured to update the access location information of the convergence terminal stored in the HSS after receiving the access location information of the convergence terminal from the second convergence access switch; and return the location update response message to the second convergence access switch after the update is completed.