Good to know: What is SIM?

20.09.2021

When it comes to our smartphones or similar devices, we immediately know what we are inserting a SIM card for. But why is a SIM card so important? In this article, we summarize the different types and formats of SIM cards and how exactly they work. And: Why do some of our mini PCs actually have a SIM card?

About the importance and structure of the SIM card 

The term SIM stands for "subscriber identity module" and means something like "subscriber identity module". SIM cards are identification cards in the form of chips for mobile phone users. Among other things, they have their own processor(CPU), a non-volatile memory (NVRAM) and a working memory(RAM).  

If the SIM card is supplied with power, it is registered in the network as a unique number (ICCD = Integrated Circuit Card Identifier). On the one hand, this number ensures the connection between the mobile device and the network operator, and on the other, it guarantees that mobile networks are not used illegally. 

Different sizes of SIM cards 

  • The standard or mini SIM has a size of 15 x 25 mm and its foundation was laid with the introduction of cell phones. 
  • At 12 x 15mm, the Micro SIM is more than 50% smaller than its predecessor, but the chip on the Micro SIM is the same size as the chip on the Mini SIM.
  • Measuring 8.8 x 12.3 mm, the nano SIM consists almost entirely of the chip. 
  • eSIM (embedded SIM) is the latest version of SIM cards and is permanently installed. It cannot be changed, but the eSIM can be overwritten. 

 

What can the eSIM do and what is the difference to the SIM card?  

As already mentioned, the "e" in eSIM stands for "embedded". An eSIM has the same function as a SIM card, but is permanently installed and cannot be replaced. The data on the eSIM can be flexibly and promptly overwritten when changing tariffs. 

The eSIM, introduced at the end of 2018, simplifies changing providers and devices as well as networking multiple devices. In addition, thanks to the compact size of the eSIM, smaller devices such as smartwatches or fitness trackers can also be equipped with more functions. The advantages of the embedded SIM include the uniformity of the SIM and the fact that the SIM card does not have to be broken out or cut to size. In addition, the well-known roaming charges can be avoided abroad, as the eSIM can also be activated and topped up with providers abroad. 

 

What is the function of SIM cards in Mini PCs? 

With vehicle PCs in particular, it can happen that there is no Internet connection nearby at the place of use. In this case, the SIM card can be inserted into the Mini PC to give it mobile Internet access. For example, in trucks that drive through several countries for navigation or for communication tools, where one of two SIM card slots is used for the EU countries and the other for a third country through which the truck has to drive. 

 

spo-comm Mini-PCs with SIM card slots 

Two SIM cards can be inserted in the PCs of the RUGGED series, the RUGGED Ryzen, RUGGED GTX1050TI and the RUGGED Q170, as well as in the MOVE series, such as the MOVE Q170 and the MOVE N3160

 

Discover the RUGGED range 

Discover the MOVE range 

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