D.6 Security of the GPRS backbone
3GPP43.020Release 17Security related network functionsTS
The operator is responsible for the security of its own Intra-PLMN backbone which includes all network elements and physical connections. The operator shall prevent unauthorised access to its Intra-PLMN backbone. A secure Intra-PLMN backbone guarantees that no intruder can eavesdrop or modify user information and signalling in the Intra-PLMN backbone.
The GPRS architecture utilises GPRS tunnelling and private IP addressing within the backbone to restrict unauthorised access to the backbone. User traffic addressed to a network element shall be discarded. Firewall functionality may provide these means at the access points (Gi reference point and Gp interface) of the Intra-PLMN backbone.
The Inter-PLMN links shall be negotiated between operators as part of the roaming agreement. They shall ensure that the Inter-PLMN links are secure providing integrity and confidentiality. For example, secure links can be achieved by point to point links, private Inter-PLMN backbones or encrypted tunnels over the public Internet.
Operators shall be able to determine the origin of packets coming from the inter-PLMN backbone. One example is to use a Frame Relay PVC between two operators.
Annex E (normative):
GSM Cordless Telephony System (CTS), (Phase 1); Security related network functions; Stage 2
This annex is defining the security related service and functions for the GSM Cordless Telephone System (CTS).
This annex is only applicable if CTS is supported.