Patent ID: 9253634
Filing Date: 2016-02-02
CPC Classification: H04W

Claim Text:
1. A method of updating a key, the method comprising: a small base station monitoring user plane uplink Packet Data Convergence Protocol (PDCP) count value or user plane downlink PDCP count value of each User Equipment (UE) connected with the small base station; and the small base station transmitting a key update request as a function of the user plane uplink PDCP count value or the user plane downlink PDCP count value to a macro base station so that the macro base station updates a key in response to the key update request or the small base station transmitting information about the user plane uplink PDCP count value or the user plane downlink PDCP count value to the macro base station so that the macro base station updates a key according to the information about the user plane uplink PDCP count value or the user plane downlink PDCP count value.