B.2 Information Elements used in the messages

23.0943GPPFollow-Me (FM)Release 17Stage 2TS

The operation code

The operation code is defined in 3GPP TS 22.030 for the control of Supplementary Services and consists of the two characters:

– ** for Registration;

– ## for Erasure;

– *# for Interrogation.

The Service Codes

The Service Code is service specific for FM.

The remote number

The remote number is the basic MSISDN of the remote party if the remote party is a GSM subscriber. It is entered by the initiating subscriber as part of the registration request. It is a number in international format.

Additional information field

An additional information field which does not exceed 30 octets may be optionally included in all FM control messages to convey operator specific information to the FFNb. The content and use of this additional information is operator specific and out of scope of the present document.

The initiating number

The initiating number is the basic MSISDN of the initiating subscriber. It is derived by HLRa from the IMSI of the initiating subscriber.

This parameter is used in international format according to the scheme:

– country code, national (significant) number.