TECHNIQUES TO ENABLE A SECURE DATA COMMUNICATION BETWEEN A FIRST NETWORK AND A SECOND NETWORK THAT COMPRISE AT LEAST IN PART A DIFFERENT COMMUNICATION ENVIRONMENT

A method and system for to enable a secure data communication between a first network of a first network provider and a second network of a second network provider,wherein the first network comprises at least a first part that is a 5G communication environment, wherein the second network comprises at least a first part that is communication environment preceding the 5G communication environment and wherein an access link to the first part of the second network comprises a GTP-firewall to protect the first part of the second network;wherein the method comprises the following step:* Establishing a handover process from the 5G communication environment of the first network to the non-5G first part of second network; ;* Directing a control plane traffic of the data transmission from a SEPP of the first network to a SEPP of the second network; wherein the SEPP of the first network encrypts the data transmission and the SEPP of the second network decrypts the encrypted data transmission;* Directing a user plane traffic of the data transmission to the access link to the non-5G first part of the second network and through the GTP-firewall;* Providing the decrypted control plane traffic to the GTP-firewall, wherein the GTP-firewall performs security measures based on information extracted from the control plane traffic.