4 Description

22.0943GPPFollow Me service descriptionRelease 17Stage 1TS

Follow Me enables an initiating mobile subscriber A to have control over the Follow Me data of a remote party B. Initiating Subscriber A shall be able to manipulate the Follow Me data of remote party B such that subsequent calls directed to remote party B are forwarded to initiating subscriber A.

Initiating subscriber A needs to have FM provisioned by her service provider. In case remote party B is a subscriber she needs to have FM provisioned by her service provider too.

The FM service supervisor shall be able to modify the Follow Me data of the remote party who has been registered to another initiating subscriber.

It remains in the responsibility of a FM provisioning service provider to confine

a.) the range of remote parties for which a FM provisioned subscriber may become initiating subscriber

b.) the range of potential initiating subscribers for a remote party.

The mobile subscriber who has been provisioned Follow Me is able to use the following control operations:

Registration available to the initiating subscriber

Interrogation available to the initiating and remote party in case the remote party corresponds to a subscriber

Erasure available to the initiating and remote party in case the remote party corresponds to a subscriber

(There is no explicit activation or deactivation.)

The FM service supervisor is able to use the following control operations:

Interrogation

Erasure (forced erasure)

NOTE 1: The functionality of the Follow Me feature is equivalent to the Call Forwarding Unconditional Supplementary Service (see 3GPP TS 22.082 [5]), controlled by initiating subscriber A and effecting remote party B.

NOTE 2: The Follow Me feature is designed in such a way that the requirements of "functional addressing", which is needed for GSM-Railway operators, can be met. The concept of "functional addressing" enables a subscriber to set up a call to a "function" – e.g. the conductor – on a "train".
The Follow Me feature identifies this "function" with the remote party B. Consequently a "functional number" is the equivalent to the number of remote party B (e.g. the MSISDN of a subscriber B). A call to that "functional number" (the conductor on a particular train – to stay with the example) will be forwarded to the MS of the person, who is on duty as a conductor at this time for this train.
In the context of the Follow Me feature, this person (the train conductor) constitutes the "initiating subscriber" A, who has registered Follow Me with respect to the remote party B (the "function" train conductor).

4.1 Normal Operation

Due to reduced security requirements to the Follow Me feature the service shall not be offered in standard operations of public 3GPP networks. In railway operations it must be enabled by definitive action on the part of the operator.

Fraud Information Gathering System (FIGS) as specified in [11] can be used to protect in CAMEL based inter-working networks.

The Follow Me feature shall be controlled by means of Subscriber Controlled Input using USSD.