Just out of curiosity, how much memory would you find in a sim card? Do they vary or are they all the same? How many SMS or address book records would it hold?
Anything from 32 Kb up to several Mb's, I believe the largest is/was 1 Gb, though most common are either 32, 64 or 128 Kb, and earlier ones were just 16 Kb, nowadays most a re 128 Kb.
It greatly depends, besides the capacity size of the SIM, on the carrier (i.e. how much memory is used by the "network" and its services) but usually you have around 250 to 500 contacts and 16 to 32 SMS's .
jaclaz
If you got very old card you can clone it. After get KI key from SIM, you can clone card and finally make an attack on PIN, rewriting it after few unsucesfull tries. Starting form 2004 new cards are using 128COMP-V2 (or newer) algo….. it's not possible to replicate such card if you mean Bruteforce method (not possible to get KI key) - card will de blocked forever within about 5-7 minutes once attack start. So in other words it's not possible to read PIN from card…
I think that it's working an another way - there are plenty of phones which are sim locked (simlock) to specified carrier - without entering correct SIM into phone you cannot sometimes run it/eneter menu etc. Solution for this are simply save to SIM a "chosen" IMSI which will be generated from MCC+MNC… after this phone will accept such card as it comes from original carrier. If you want to generate IMSI at your own you can get it by such free tool - http//