Method and system for establishing a connection between network elements

Abstract

The invention provides a method and system for establishing or handling a connection between a first and a second network element connected to different networks such as GPRS/UMTS and IP-based networks. The connection is established by means of at least one third network element such as a SGSN or GGSN arranged in one of the networks. The third network element is adapted to send, when receiving information on an establishment of a connection, a request to a fourth network element which may be a Call State Control Function (CSCF), a Policy Control Function (PCF), or a Call Processing Server (CPS). The request requests permission for establishing a requested type of connection, or requests a check of a connection parameter, and specifies the first and/or second network element and/or the connection or connection type to be established. The fourth network element returns a response specifying a permission for establishing a connection or connection type, or specifying a connection parameter.

1 . A method for establishing a connection in a two-layer communication network comprising a first communication network layer adapted to establish a communication channel to a terminal and a second communication network layer adapted to establish a session carried on said communication channel, said method comprising the steps of
 establishing a session with an identifier,   establishing a communication channel with said identifier,   authorizing said communication channel by said session using said identifier.   
   
   
       2 . A method according to  claim 1 , wherein said authorizing comprises the steps of:
 a network element in said first communication network layer (e.g. GGSN) initiating a request for said authorization at communication channel establishment   a network element in said second communication network layer (e.g. CSCF) performing said authorization.   
   
   
       3 . A method according to  claim 1 , wherein said first communication network layer is a GPRS/UMTS layer, and said second communication network layer is an IP Multimedia Subsystem. 
   
   
       4 . A method according to  claim 1 , wherein said terminal is a User equipment or Mobile Station. 
   
   
       5 . A system for establishing a connection in a two-layer communication network comprising a first communication network layer adapted to establish a communication channel to a terminal and a second communication network layer adapted to establish a session carried on said communication channel, said system being adapted:
 to establish a session with an identifier,   to establish a communication channel with said identifier,   to authorize said communication channel by said session using said identifier.   
   
   
       6 . A system according to  claim 5 , wherein for performing said authorizing:
 a network element in said first communication network layer is adapted to initiate a request for said authorization at communication channel establishment   a network element in said second communication network layer is adapted to perform said authorization.   
   
   
       7 . A system according to  claim 5 , wherein said first communication network layer is a GPRS/UMTS layer, and said second communication network layer is an IP Multimedia Subsystem. 
   
   
       8 . A system according to  claim 5 , wherein said terminal is a User equipment or Mobile Station.