Of the descriptions I have read explaining GSM Milenage, none clearly explain what is involved in implementing it at a network level. The info that is required to accomplish this is not the nuts and bolts of how the authentication or key generation work (which is more of a software design interest when implementing Milenage) but rather which nodes in the network are affected and what is addition..

This page covers timers used in GSM which include T100, T200, T301, T3126, T3146, T3182, T3190, T3192, T3124, T3230 and T3330. TimerFunction/valueT100 It helps detect presence of the GSM radio Link by checking SACCH frames every 480 milli-sec. (Radio link timeout)T200 It is used as retransmission on data link layer. Value varies depending on different messages (for FACCH it is set to 155ms)T301 ..

What is IMEI? The International Mobile Station Equipment Identity or IMEI is a number, usually unique,to identify 3GPP (i.e., GSM, UMTS and LTE) and iDEN mobile phones, as well as some satellite phones. It is usually found printed inside the battery compartment of the phone, but can also be displayed on-screen on most phones by entering *#06# on the dial-pad, or alongside other system informatio..

In spec. 04.90 or 24.90, it came up in 6.2 section. 6.2 Cross phase compatibility6.2.1 Network only supports protocol version 1 of unstructured supplementary service data operations If a mobile initiated USSD request using protocol version 2 is rejected by the network, and the reason for the rejection is indicated either by the problem code "unrecognized operation" or a cause "Facility rejected"..

*#06# IMEI가 없는 폰(양산될 때 IMEI가 찍히지 않는 폰)으로 심을 싸서 끼워보면,사업자별로, SIM card Registration failure가 나오는 사업자심이 있고, 정상동작하는 사업자 SIM이 있습니다.프랑스에서 SFR심은 SIM card Registration Failure 나왔고, Orange나 Bouygtel은 대부분 정상동작 한다고 합니다.이는 SIM에 관련 된 사항은 아니고, 해당 사업자가 해당 IMEI로 등록을 허용 하느냐 마느냐의 문제입니다.간혹 사람들이 SIM에 따른다고 이야기하는 것은, 해당 사업자 SIM에 따라 등록되는 망이 결정되어지기 때문입니다.

This is a NAS message which is sent to UE when the UE is not allowed to register to the specific network or a specific Location Area. Network send this message when a UE tries to camp on the PLMN (usually VPLMN) which is not allowed for the UE. When it recieves, UE has to do following steps.i) UE has to store this PLMN in forbidden PLMN list in USIMUE has to rem..