Patent ID: 8493854

Claim:
A method for communicating information in a mobile communication system, the method comprising: transmitting, from a user equipment (UE) to a base station (BS), a preamble over a random access channel (RACH), the preamble randomly selected from a plurality of preamble candidates; receiving, at the UE, a first response message from the BS in response to the preamble, the first response message including a Medium Access Control (MAC) identifier (MAC Id) and an indicator, the indicator indicating that the MAC Id is included; transmitting, from the UE to the BS, data including the MAC Id and the indicator; and receiving, at the UE, a second response message from the BS in response to the data, the second response message including a UE identifier and the indicator, the indicator indicating that the UE identifier is included, wherein the MAC Id is based on the preamble and is for identifying the preamble transmitted by the UE, wherein the UE identifier is for identifying the UE in a cell, and wherein a bit length of the MAC Id is equal to a bit length of the UE identifier.