Method and apparatus for random access layered preambles

An operation method of a base station in a communication system, the operation method comprising:

• configuring preamble groups, preambles belonging to each of the preamble groups, and a QoS of each of the preamble groups;
• transmitting preamble group configuration information to a terminal, the preamble group configuration information including information on the preamble groups, information on the preambles belonging to each of the preamble groups, and QoS information on the QoS of each of the preamble groups;
• receiving, from the terminal, a first message including a preamble selected based on the preamble group configuration information and a QoS of the terminal;
• detecting the preamble in the first message;
• and
• transmitting, to the terminal, a second message that is a response to the first message.

A terminal, the terminal comprising a processor, a memory electronically communicating with the processor, and instructions stored in the memory, wherein when executed by the processor, the instructions cause the terminal to:

• receive, from a base station, quality of service (QoS) information for preamble groups and information on preambles belonging to each of the preamble groups;
• select one preamble group from among the preamble groups based on the QoS information and a QoS of the terminal;
• select a preamble within the one preamble group based on the information on preambles belonging to each of the preamble groups;
• transmit a first message including the selected preamble to the base station;
• and
• receive, from the base station, a second message that is a response to the first message.