I have a question regarding a location update in a roaming situation for a mobile station, what will be the signaling messages allowing this procedure to take place? I know that 4 of the messages are LOCATION UPDATING REQUEST Global Title Translation AUTHENTICATION REQUEST CHANNEL REQUEST but I don't know how these messages will be used and the scope for using each of them.
The best place to look is likely the 3GPP specs, and it is worth checking exactly which type of network and what specs they are using if you can.
The principles will stay the same across releases, but can differ between GSM, UMTS etc.
The specs are available online at the 3GPP site, free of charge, here: https://www.3gpp.org/specifications
A quick link to a recent spec covering location procedures is here: https://www.etsi.org/deliver/etsi_ts/123000_123099/123012/15.00.00_60/ts_123012v150000p.pdf