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Slave-of-Allaah
02-25-2004, 08:50
Hello,

I would like to thank Mr. Daniel Jabif (SimEmu) for his Works.


I few Questions for him and the other Guys who are Familiar with the Sim-Emu And the Whole GSM SIM Card File Entry Stracture.


1) Why the IMSI input Field of the Sim-Emu is a fixed to 18 Decimal Digits?

2) Why the First two Digits of that 18 Digits of the IMSI Field Accepts ONLY two Unique Digits which are "08" ?

3) Does this have some thing to do with the OLD Comp128 V1 GSM Algorithm ?

4) Can we/you rewrite the Sim-Emu to Accept any Decimal Digits inputed regardless of what the first two digits and the Length will be?




Thank you for your Understanding


Slave-of-Allaah

simemu
02-25-2004, 17:05
Hi

1) That is the maximum allowed in GSM specification.

2) It is an excess of validation. Do you know an operator that uses an IMSI of less than "08" ? Give me please an example of that IMSI.

3) No

4) In the next version of SIM-EMU I'll fix that problem, in particular, the possibilty to introduce F's in the end.

Regards

Slave-of-Allaah
02-25-2004, 17:17
Yes Simemu,

I am glad to tell you that I am currently able to have an IMSI with ONLY 15 Digits!

That is the product of: MCC+MNC+ XXXXXXXXXX of the Operator's Numbering Plan of his choise!

This will make up 15 Digits IMSI XXX+XX+XXXXXXXXXX Totaly Decimal Digits NO even last Digit is an Alpha


Welcome Daniel

By Slave-of-Allaah

Slave-of-Allaah
02-25-2004, 17:50
Hi

1) That is the maximum allowed in GSM specification.

2) It is an excess of validation. Do you know an operator that uses an IMSI of less than "08" ? Give me please an example of that IMSI.

3) No

4) In the next version of SIM-EMU I'll fix that problem, in particular, the possibilty to introduce F's in the end.

Regards





I don't have any problem with the 18 Digit IMSI limit of the GSM Spec. but the problem is: You can't input less than 18 Digits into that Field of the SIM-EMU and that is where the problem is. If you try to input less than 18 Digits in the IMSI Field of the Sim-Emu you aren't allowed to pass this step to the next Ki Field.


It will be fine if you can omit the 08 because there is an IMSI which doesn't start with that 08.



Regards
By Slave-of-Allaah

simemu
02-25-2004, 18:01
The 15 digits IMSI that you say is the external format of IMSI.
In SIM-EMU you have to enter the internal format of IMSI.

Read this post http://forum.gsmhosting.com/vbb/showthread.php?t=51024

Regards

Slave-of-Allaah
02-25-2004, 18:08
OK Simemu, I will be trying to convert my External IMSI Format inot the SIM-EMU Internal format as you directed me by the above thread.



Thank you


I will keep asking you more!