A vehicle includes a driving motor, a battery for the driving motor, a solar cell, and a control device for controlling charge of the battery using the solar cell and an external charge facility. The method and apparatus provide encoding an image by using a code factor table in conjunction with a set of element codes. The intermediate relay node establishes a tunnel to the downstream relay node in association with the relay-node address of the downstream relay node, updates the reply message by removing the relay-node address of the down stream relay node from the reply message, and transfers the updated reply message to an adjacent upstream relay node along the packet transfer route.