We know the basics of the SIM now.But there's more to this chip than imagined.Communication itself is a beautiful thing.Anything associated with it would be complex.   Its a chip that allows you to make calls,receive calls or messages,allows you to enjoy value added services;its also a storage device for all your information,messages and contacts etc. We also know what  IMSI,PIN and PUK is.   Incase you are to travel abroad and wish to use your own number , your operator will provide you with a Dual IMSI SIM which is a SIM that allows you to connect internationally once you are out of the Indian network.Then how is your number traced?   If you look at your SIM,you can see a chip having some circuits in it.Well that is where all the math is. The most amazing part is that this circuit is designed uniquely for every single SIM that exists.   How is a SIM Identified?   The SIM is identified by the its ICC-ID (Integrated Circuit Card ID).The identification id consists of an algorithm which is used to identify your number.This is used internationally.So incase you use the same number abroad logging into another operator's network, make no mistake,you will be traced.Now you understand how the long distance bill comes....right?   There is a coding to the 19 digit engraving on the SIM.The entire number is not the SIM number.   The first two digits identifies the Telecom code (given internationally to all countries),in our case its 89 The next two digits mention the country code- in our case 91 The next two digits would indicate the network code. The next four digits give the details of the month and year of manufacturing. The next two digits give the details of switch configuration of the operator. Finally the next six digits refers to the SIM number. And the last digit which is separated from the rest is called the “check digit”. So,When this chip connects to a network to make a call,it gets traced thanks to the unique logic above.   Now you didn't know that,did you?Told you,its a beautiful technology.Now you might also know how the cops get to trace out numbers when required.   Hmm...whats the point to all this,The point is that technology like any other thing should not be misused.By now ,dear reader,you might have understood the magnitude of this technology.Safety hence lies in your hands.As I mentioned in the Part 1 of this article,you have to safeguard your number.   There are many hazards that you may face incase your number is misused.I also mentioned that procuring a SIM is very easy.   Please keep your documents safe.Donot hand over photo-copies of your personal details and let it be.There are so many times your documents might get rejected.Please demand for rejected copies.If an agent is getting you the number,do not hand over original documents to them.If you are careless,you may end up paying way more than what you bargained for.   Be very careful,this chip is easily available but in no way is it an ordinary chip.Safeguarding your property lies in your hand so be aware and enjoy the services you pay for.