A communication method, comprising: receiving, by a core network device, a first message from an access network device, wherein the first message carries information used to indicate a slice supported by the access network device; and determining, by the core network device, a location area identity list of user equipment, UE, based on the information about the slice supported by the access network device; wherein the first message is a connection setup request message, the connection setup request message is used by the access network device to set up a connection to the core network device, and the method further comprises: sending, by the core network device, a connection setup response message to the access network device, wherein the connection setup response message carries information used to indicate a slice supported by the core network device, and the information about the slice supported by the core network device is used by the access network device to select the core network device for the UE; wherein the method further comprises: sending, by the core network device, a configuration update message to the access network device, wherein the configuration update message is used to update the information about the slice supported by the core network device, and sending, by the core network device, indication information to the access network device, wherein the indication information is used to instruct the access network device to reselect a core network device for the UE; and/or wherein the method further comprises: receiving, by the core network device, a configuration update message from the access network device, wherein the configuration update message is used to update the information about the slice supported by the access network device. receiving, by a core network device, a first message from an access network device, wherein the first message carries information used to indicate a slice supported by the access network device; and determining, by the core network device, a location area identity list of user equipment, UE, based on the information about the slice supported by the access network device; wherein the first message is a connection setup request message, the connection setup request message is used by the access network device to set up a connection to the core network device, and the method further comprises: sending, by the core network device, a connection setup response message to the access network device, wherein the connection setup response message carries information used to indicate a slice supported by the core network device, and the information about the slice supported by the core network device is used by the access network device to select the core network device for the UE; wherein the method further comprises: sending, by the core network device, a configuration update message to the access network device, wherein the configuration update message is used to update the information about the slice supported by the core network device, and sending, by the core network device, indication information to the access network device, wherein the indication information is used to instruct the access network device to reselect a core network device for the UE; and/or sending, by the core network device, a configuration update message to the access network device, wherein the configuration update message is used to update the information about the slice supported by the core network device, and sending, by the core network device, indication information to the access network device, wherein the indication information is used to instruct the access network device to reselect a core network device for the UE; and/or wherein the method further comprises: receiving, by the core network device, a configuration update message from the access network device, wherein the configuration update message is used to update the information about the slice supported by the access network device. receiving, by the core network device, a configuration update message from the access network device, wherein the configuration update message is used to update the information about the slice supported by the access network device.