Patent ID: 8619703
Filing Date: 2013-12-31
Classification: H04L,H04W

Abstract:
1. A communications system comprising: a network switcher for communicating with a wireless terminal device of a mobile unit; and a plurality of access point (AP) devices, each AP device including wherein when the terminal device hands over from the source AP device to the destination AP device, the destination AP device is configured to transmit physical address information of the terminal device to the source AP device, the source AP device is configured to receive the physical address information, look up, in response to the received physical address information, the table of the source AP device with the received physical address information and then send back to the destination AP device physical and network address information of the terminal device, which is stored in the table of the source AP device, when the destination AP device receives from the source AP device the physical and network address information of the terminal device, the destination AP device is configured to store the received physical and network address information in the table of the destination AP device, after sending back to the destination AP device the physical and network address information, the source AP device is configured to transmit network address information of the terminal device, which is stored in the table of the source AP device, to the destination AP device, when the destination AP device receives the network address information of the terminal device, which has been transmitted by the source AP device after sending back to the destination AP device the physical and network address information, the destination AP device is configured to transmit to the source AP device predetermined information including the physical address information of the terminal device, stored in the table of the destination AP device, when the source AP device receives the predetermined information, the source AP device is configured to determine whether storing of the connection information of the terminal device in the table of the destination AP device is completed, and to delete the connection information stored in the table of the source AP device when it is determined that the storing is completed, the destination AP device is configured to transmit to the source AP device a Proxy address resolution protocol (ARP) request, the Proxy ARP request including said physical address information of the terminal as source physical address information of the Proxy ARP request and broadcast address information as destination physical address information of the Proxy ARP request, the source AP device is configured to receive the Proxy ARP request, look up the table of the source AP device with the physical address information of the terminal included in the received Proxy APR request, and then send back to the destination AP device Proxy ARP data corresponding to physical and network address information of the terminal device, when the Proxy ARP data corresponding to physical and network address information of the terminal device exist in the table of the source AP device, when the destination AP device receives from the source AP device the Proxy ARP data corresponding to the physical and network address information of the terminal device, the destination AP device is configured to store the received Proxy ARP data in the table of the destination AP device, after sending back the Proxy ARP data to the destination AP device, the source AP device is configured to transmit a further ARP request to the destination AP device, the further ARP request including broadcast address information as destination physical address information of the further ARP request, media access control (MAC) address information of the destination AP device as source physical address information of the further ARP request, and the network address information of the terminal device, which is stored in the table of the source AP device, as destination network address information of the further ARP request, when the destination AP device receives the further ARP request, the destination AP device is configured to transmit to the source AP device an ARP reply including the physical address information of the terminal device, stored in the table of the destination AP device, and when the source AP device receives the ARP reply, the source AP device is configured to determine whether storing of the connection information of the terminal device in the table of the destination AP device is completed, and to delete, when it is determined that the storing is completed, from the table of the source AP device the Proxy ARP data corresponding to the physical address information of the terminal device included in the ARP reply as the connection information stored in the table of the source AP device.