Patent ID: 7499448

Claim:
A method for data exchange between network elements, wherein a first network element is arranged in a first network domain with an address valid in the first network domain, wherein a second network element is arranged in a second network domain with an address valid in the second network domain, wherein a network node device is arranged between the network domains for forwarding a data packet to be sent by the first network element to the second network element, wherein the data packet comprises a characterizing part and a data part, wherein a destination address characterizing a receiving network element in the characterizing part of the data packet is translated under the control of the network node device into a destination address valid in the second network domain, the method comprising an address discovery comprising: sending a message by the first network element to the second network element arranged in the second network domain with a destination address of the second network element that is contained in the data part and is valid in the first network domain; receiving the message by the second network element and storing the destination address of the second network element valid in the first network domain; sending a response message by the second network element to the first network element with a destination address of the first network element that is contained in the data part and is valid in the second network domain; and receiving the response message by the first network element and storing the destination address of the first network element valid in the second network domain, the method further comprising entering into the data part by the first network element a source address of the first network element valid in the second network domain.