Method and apparatus for controlling network access in a wireless communication system

1. A method of performing a random access procedure for network access at a User Equipment (UE) in a wireless communication system, the method comprising:

receiving a first downlink signal including first information at a time t 1 , the first information indicating a first time duration T 1 ;

receiving a second downlink signal including second information at a time t 1 +b within T 1 , the second information indicating a second time duration T 2 ; and

performing the random access procedure for network access,

wherein b is a time duration taken to receive the second downlink signal after t 1 ,

wherein if T 2 is larger than b, the random access procedure is allowed after T 2 −b has passed from t 1 +b,

wherein if T 2 is equal to or less than b, the random access procedure is allowed after t 1 +b.

2. The method of claim 1 , wherein the first downlink signal includes a message for rejecting a radio resource control (RRC) connection request or a message for releasing a RRC connection.

3. The method of claim 1 , wherein the first downlink signal includes a system information block, and the first information further indicates whether the random access process is allowed or barred during T 1 from t 1 .

4. The method of claim 1 , wherein the network access is for a machine type communication (MTC).

5. The method of claim 1 , wherein the UE is a delay-tolerant device.

6. A User Equipment (UE) configured to perform a random access procedure for network access in a wireless communication system, the UE comprising:

a radio frequency (RF) unit; and

a processor, wherein the processor is configured to:

receive a first downlink signal including first information at a time t 1 , the first information indicating a first time duration T 1 ,

receive a second downlink signal including second information at a time t 1 +b within T 1 , the second information indicating a second time duration T 2 , and

perform the random access procedure for network access,

wherein b is a time duration taken to receive the second downlink signal after t 1 ,

wherein if T 2 is larger than b, the random access procedure is allowed after T 2 −b has passed from t 1 +b,

wherein if T 2 is equal to or less than b, the random access procedure is allowed after t 1 +b.

7. The UE of claim 6 , wherein the first downlink signal includes a message for rejecting a radio resource control (RRC) connection request or a message for releasing a RRC connection.

8. The UE of claim 6 , wherein the first downlink signal includes a system information block, and the first information further indicates whether the random access process is allowed or barred during T 1 from t 1 .

9. The UE of claim 6 , wherein the network access is for a machine type communication (MTC).

10. The UE of claim 6 , wherein the UE is a delay-tolerant device.

11. A method of controlling a random access procedure for network access in a wireless communication system, the method comprising:

transmitting, by a Base Station (BS), a first signal to a User Equipment (UE) at a time t 1 , the first signal indicating a first time duration T 1 ;

transmitting, by the BS, a second signal to a Mobility Management Entity (MME), the second signal including identification information of the UE;

transmitting, by the BS, a third signal to the MME if the BS detects network access congestion relief, the third signal informing the network access congestion relief;

receiving, by the BS, a fourth signal from the MME, the fourth signal indicating a second time duration T 2 for the UE; and

transmitting, by the BS, a fifth signal to the UE at a time t 1 +b, the fifth signal indicating the second time duration T 2 ,

wherein b is a time duration taken to receive the second downlink signal after t 1 ,

wherein if T 2 is larger than b, the UE is allowed to perform the random access procedure after T 2 −b has passed from t 1 +b,

wherein if T 2 is equal to or less than b, the UE is allowed to perform the random access procedure after t 1 +b.

12. The method of claim 11 , wherein the first signal includes a message for rejecting a radio resource control (RRC) connection request or a message for releasing a RRC connection.

13. The method of claim 11 , wherein the first signal includes a system information block, and the first signal further indicates whether the random access process is allowed or barred during T 1 from t 1 .

14. The method of claim 11 , wherein the network access is for a machine type communication (MTC).

15. The method of claim 11 , wherein the UE is a delay-tolerant device.

16. A wireless communication system configured to control a random access procedure for network access, the wireless communication system comprising:

a User Equipment (UE);

a Base Station (BS); and

a Mobility Management Entity (MME),

wherein the BS is configured to:

transmit a first signal to a User Equipment (UE) at a time t 1 , the first signal indicating a first time duration T 1 ,

transmit a second signal to the MME, the second signal including identification information of the UE,

transmit a third signal to the MME if the BS detects network access congestion relief, the third signal informing the network access congestion relief,

receive a fourth signal from the MME, the fourth signal indicating a second time duration T 2 for the UE, and

transmit a fifth signal to the UE at a time t 1 +b, the fifth signal indicating the second time duration T 2 ,

wherein b is a time duration taken to receive the second downlink signal after t 1 ,

wherein if T 2 is larger than b, the UE is allowed to perform the random access procedure after T 2 −b has passed from t 1 +b,

wherein if T 2 is equal to or less than b, the UE is allowed to perform the random access procedure after t 1 +b.

17. The wireless communication system of claim 16 , wherein the first signal includes a message for rejecting a radio resource control (RRC) connection request or a message for releasing a RRC connection.

18. The wireless communication system of claim 16 , wherein the first signal includes a system information block, and the f first signal further indicates whether the random access process is allowed or barred during T 1 from t 1 .

19. The wireless communication system of claim 16 , wherein the network access is for a machine type communication (MTC).

20. The wireless communication system of claim 16 , wherein the UE is a delay-tolerant device.