A packet communication method for a data between a home node and a destination node, which is performed via a communication network connected with an identity server (H-IS or F-IS) storing a bundle of locators and memorizing a node identifier of nodes belonging to a network, comprising: a step in which a home node provides a node identifier of the home node and sends a locator assignment request to said identity server (H-IS or F-IS); a step in which said identity server (H-IS or F-IS) assigns the locator to said home node and stores correspondence relationship consisting of different types of IDs, e.g. alD, pID, kind of hash function used to generate the IDs, and verification information such as cryptographic keys and certificates, between the node identifier and the locator; a step in which said home node provides the node identifier of the relevant destination node and sends a locator resolution request to the identity server (dH-IS) of the destination node to request resolution of the locator corresponding to the node identifier of the destination node; a step in which said identity server (dH-IS) of the destination node assigns the locator to said destination node, and stores correspondence relationship consisting of different types of IDs, e.g. aID, pID, kind of hash function used to generate the IDs, and verification information such as cryptographic keys and certificates, between the node identifier and the locator; a step in which a packet header, where a destination address and a home address have been specified by the node identifier of said destination node and the node identifier of said home node, is rewritten to the locator of said destination node and the locator of said home node; and a step in which the packet header conducts a routing according to the locator, wherein said identity servers provide node ID to locator mappings not only to the inquiring nodes, but also the gateways under which the nodes are located, and said identity servers located in the foreign network (F-IS) and home network (H-IS) communicate to each other to verify a visiting node's credential in the foreign network and to let the H-IS know about the current locators of its home node when they are visiting in the foreign network. a step in which a home node provides a node identifier of the home node and sends a locator assignment request to said identity server (H-IS or F-IS); a step in which said identity server (H-IS or F-IS) assigns the locator to said home node and stores correspondence relationship consisting of different types of IDs, e.g. alD, pID, kind of hash function used to generate the IDs, and verification information such as cryptographic keys and certificates, between the node identifier and the locator; a step in which said home node provides the node identifier of the relevant destination node and sends a locator resolution request to the identity server (dH-IS) of the destination node to request resolution of the locator corresponding to the node identifier of the destination node; a step in which said identity server (dH-IS) of the destination node assigns the locator to said destination node, and stores correspondence relationship consisting of different types of IDs, e.g. aID, pID, kind of hash function used to generate the IDs, and verification information such as cryptographic keys and certificates, between the node identifier and the locator; a step in which a packet header, where a destination address and a home address have been specified by the node identifier of said destination node and the node identifier of said home node, is rewritten to the locator of said destination node and the locator of said home node; and a step in which the packet header conducts a routing according to the locator, wherein said identity servers provide node ID to locator mappings not only to the inquiring nodes, but also the gateways under which the nodes are located, and said identity servers located in the foreign network (F-IS) and home network (H-IS) communicate to each other to verify a visiting node's credential in the foreign network and to let the H-IS know about the current locators of its home node when they are visiting in the foreign network.