A method carried out by a first terminal for receiving and transmitting a relay service code wherein the first terminal is adapted to perform a user equipment-to-network relay function, UE-to-network relay function, the method comprising: transmitting a service authorization request message to a first network device comprising a proximity-based service, ProSe, function; and receiving a service authorization response message from the first network device wherein the service authorization response message includes: - validity time information related to a corresponding relay service code; - an access point name, APN, the first terminal needs to use to request a PDN connection to receive a corresponding service; - information related to usage regarding services which can be received from the first terminal to a second terminal through a relay service code value; - a corresponding relay service code that the first terminal provides, when providing a relay service to a second terminal; transmitting a PDN connectivity request message including the APN to a mobility management entity, MME; receiving a default EPS bearer activation request from the MME; selecting a P-GW and setting up a PDN connection via a default EPS bearer activation; performing a discovery for a UE-to-network relay with the second terminal via a broadcast message wherein said broadcast message comprises at least the relay service code; and transmitting a service authorization request message to the first network device for changing the relay service code value, the service authorization request message including a relay service code value to be released; and receiving from the the first network device a service authorization response message comprising an altered relay service code value. transmitting a service authorization request message to a first network device comprising a proximity-based service, ProSe, function; and receiving a service authorization response message from the first network device wherein the service authorization response message includes: - validity time information related to a corresponding relay service code; - an access point name, APN, the first terminal needs to use to request a PDN connection to receive a corresponding service; - information related to usage regarding services which can be received from the first terminal to a second terminal through a relay service code value; - a corresponding relay service code that the first terminal provides, when providing a relay service to a second terminal; - validity time information related to a corresponding relay service code; - an access point name, APN, the first terminal needs to use to request a PDN connection to receive a corresponding service; - information related to usage regarding services which can be received from the first terminal to a second terminal through a relay service code value; - a corresponding relay service code that the first terminal provides, when providing a relay service to a second terminal; transmitting a PDN connectivity request message including the APN to a mobility management entity, MME; receiving a default EPS bearer activation request from the MME; selecting a P-GW and setting up a PDN connection via a default EPS bearer activation; performing a discovery for a UE-to-network relay with the second terminal via a broadcast message wherein said broadcast message comprises at least the relay service code; and transmitting a service authorization request message to the first network device for changing the relay service code value, the service authorization request message including a relay service code value to be released; and receiving from the the first network device a service authorization response message comprising an altered relay service code value.