Patent ID: 9319921
Filing Date: 2016-04-19
CPC Classification: H04L,H04W

Claim Text:
1. A mobile communication system comprising: a plurality of EPC (Evolved Packet Core) nodes configured to form an EPC network, the EPC network forming a core of an LTE (Long Term Evolution) network for mobile communication; and a DNS (Domain Name Server) server configured to select from among the plurality of EPC nodes the EPC node to use based on a selection priority in a registered DNS resource record, wherein each of the plurality of EPC nodes includes a DDNS (Dynamic DNS) client function configured to transmit an update request for the DNS resource record to the DNS server to lower the selection priority of the DNS resource record relating to a respective EPC node when the respective EPC node detects that resource usage of the respective EPC node exceeds an overloaded threshold previously specified to detect that the resource usage of the respective EPC node is approaching an overloaded state, wherein the DNS server includes a DDNS server function configured to dynamically update, in response to the update request, the DNS resource record when the DNS server receives the update request for the DNS resource record from the respective EPC node, wherein the DNS server further includes as the DNS resource record, in addition to an NAPTR (Naming Authority Pointer) record and an SRV (Service) record to which the selection priority is registered, a supplementary NAPTR record to which a domain name of the DNS resource record relating to the respective EPC node allocated with an EPC node name is previously set, and when the DNS server receives an NAPTR record query including the EPC node name of the respective EPC node from the respective EPC node, the DNS server extracts at least the supplementary NAPTR relating to the EPC node name included in the NAPTR record query and returns the extracted supplementary NAPTR to the querying EPC node.