Communication system with improved medium access control sub-layer

Abstract

A communication system which has a plurality of mobile terminals and a base station, each of the mobile terminals and/or base station comprising a medium access control sub-layer, upper layers of the medium access control sub-layer, and a lower layer of the medium access control sub-layer, wherein the medium access control sub-layer is configured to perform self-basic functions in response to basic function execution requests or functions associated with the upper layers or lower layer in response to requests therefrom. According to the present invention, the communication system can provide a compatible multimedia communication service even if an originating terminal and a terminating terminal employ different communication manners, they are available from different manufacturers or they are operated by different communication service operators.

1 - 13 . (canceled)  
   
   
       14 . A method for updating system information in a mobile terminal of a wireless communication system, the method comprising: 
 receiving a message related to system information from a network, the message comprising a system information identifier;    comparing the system information identifier to a stored identifier, wherein the stored identifier is related to system information currently stored in the mobile terminal; and    determining whether to use the system information currently stored in the mobile terminal according to a result of the comparison.    
   
   
       15 . The method of  claim 14 , further comprising using the system information currently stored in the mobile terminal if the system information identifier is the same as the stored identifier.  
   
   
       16 . The method of  claim 14 , further comprising updating the system information currently stored in the mobile terminal if the system information identifier is different from the stored identifier.  
   
   
       17 . The method of  claim 16 , wherein updating the system information comprises transmitting a request to the network.  
   
   
       18 . The method of  claim 17 , further comprising receiving the system information from the network.  
   
   
       19 . The method of  claim 14 , wherein the message is received periodically from the network.  
   
   
       20 . The method of  claim 14 , wherein the system information is related to information for accessing the network.  
   
   
       21 . A method for updating system information in a mobile terminal of a wireless communication system, the method comprising: 
 transmitting a message related to system information to a mobile terminal, the message comprising a system information identifier,    wherein the mobile terminal compares the system information identifier to an identifier stored in the mobile terminal, the stored identifier related to system information currently stored in the mobile terminal,    wherein the mobile terminal determines whether to use the system information currently stored in the mobile terminal according to a result of the comparison.    
   
   
       22 . The method of  claim 21 , wherein the message is transmitted periodically to the mobile terminal.  
   
   
       23 . The method of  claim 21 , wherein the system information is related to information for accessing the network.  
   
   
       24 . The method of  claim 21 , wherein the mobile terminal uses the system information currently stored in the mobile terminal if the system information identifier is the same as the stored identifier.  
   
   
       25 . The method of  claim 21 , wherein the mobile terminal updates the system information currently stored in the mobile terminal if the system information identifier is different from the stored identifier.  
   
   
       26 . The method of  claim 25 , wherein updating the system information comprises transmitting a request to the network.  
   
   
       27 . The method of  claim 26 , wherein the network transmits the system information to the mobile terminal.