View Full Version : USB wireless web modem and its SIM card -how it works, please?

2nd August 2010, 02:27 PM
There are these plug-in USB wireless web modems from Telstra sold for about $80 which tey say can be used with Mac pro laptop

I understand the registration and how to top-up the modem and was thinking USB wireless web modems are just plug-and-use but there is this SIM card mentioned.

What this SIM card is (and does) - is it some separate piece of hardware which is inserted into the USB modem? As a user do I have to plug in and out this SIM card somehow?

I agree that a techno - competent person may find this question silly :-) but I really want to understand this SIM card-in-the modem matter and any plain English explanation by Mac techies is appreciated!

Thanks to all who will help!

2nd August 2010, 08:54 PM
Your typical USB-based wireless internet modem is essentially a 3G mobile phone (cel phone for non-Aussies) without the normal phone bits of screen, speaker, and microphone. While some phone companies sell mobile phones that don't need a SIM card, most do, and the SIM card holds an unique identifier code that the phone network uses to match who is using the network with who they have to send the bill to every month.

When you sign up for 3G wireless internet, you have to enter a contract with the telephone company providing the internet service. The contract records the number in the SIM and the other identifier number (the IMEI number) that's built into the 3G modem itself.

When you plug the modem into the Mac, then run the software to 'activate' it, you can use the "Internet Connect" program to hook your Mac up to the wireless internet system. You don't need to have a username and password like you do with, say, ADSL or cable, because all of that is linked to the SIM card, and it sends its unique number to the network when it signs in.

4th August 2010, 04:15 PM
Thanks Brains - very informative!

So, If I understand correctly, this SIM card is not something I have to handle/remove/insert separately but is integral part of the modem which just stays inside.

Is it so?


4th August 2010, 04:22 PM
yup. you are correct. you don't ever remove it unless your modem breaks and you want to put it into new modem. The likelihood of that happening is pretty low, but even if it does (modems require replacement every couple of years just like a phone does), they could do it for you at the Telstra store when you purchase the new (or replacement) modem.