System and method for checking the permissibility of a use of a service

1. A method for checking permissibility to use a service, the service being implemented in at least one communications network, the communication network having an overall transmission capacity, the use of the service comprising transmission of at least one service-specific traffic stream which is assigned to the service by an access node which is assigned to the service to the communication network, comprising:

analyzing the use of the service with an access control function which is assigned to the access node; and

checking, via the access control function, without further interrogations at internal transmission nodes of the communications network, whether the use of the service is permitted, the checking performed taking into account an available capacity, which is

determined taking into account the overall transmission capacity, and

available to the access node for transmitting traffic streams to the communications network.

2. The method as claimed in claim 1 , wherein the service is embodied as a transmission of information which is brought about using traffic streams which are transmitted with priority.

3. The method as claimed in claim 2 , wherein the access control function signals the permissibility of the traffic stream to be transmitted with priority during use of the service to the assigned access node, and the access node subsequently transmits the traffic stream with priority to DiffServ network.

4. The method as claimed in claim 1 , wherein the overall transmission capacity depends at least partially on the transmission capacities of transmission paths of the communications network.

5. The method as claimed in claim 1 , wherein the checking of the permissibilty is carried out taking into account a service quality level which is determined by the access control function.

6. The method as claimed in claim 4 , wherein a desired service quality level is specified when the use of the service is applied for, the service quality level is taken into account by the access control function in the determination of necessary service quality level.

7. The method as claimed in claim 1 , wherein the communications network is embodied as a DiffServ network which transmits traffic streams with an ensured service quality level in a packet-oriented fashion.

8. The method as claimed in claim 7 , wherein the access control function signals the permissibility of the traffic stream to be transmitted with priority during use of the service to the assigned access node, and the access node subsequently transmits the traffic stream with priority to DiffServ network.

9. The method as claimed in claim 1 , wherein the access control function is implemented within a gatekeeper.

10. A device comprising:

at least one means for checking permissibility of use of a service which is implemented in at least one communications network having an overall transmission capacity, wherein the at least one means:

transmits at least one service-specific traffic stream which is assigned to the service by an access node assigned to the service to the communications network;

analyzes the use of the service with an access control function which is assigned to the access node; and

checks the access and via control function, without further interrogations at internal transmission nodes of the communications network, whether the use of the service is permitted, the checking performed taking into account an available capacity,

the overall transmission capacity, and

which is made available to the access node for transmitting traffic streams to the communications network.

11. The device as claimed in claim 10 , wherein the device is configured for connection to at least one other device by at least one transmission path to perform at least a portion of the checking.

12. The device of claim 10 , wherein the device is a gatekeeper.

13. The device of claim 10 , wherein the device is a transmission node.