All terms

SIM farm

A SIM farm is a bank of modems holding hundreds of physical SIM cards, used to receive or send SMS on those numbers automatically.

In detail

It is one of the ways numbers reach a marketplace; the other common route is a direct arrangement with an operator. Farms are cheap to run and easy for a carrier to spot, because hundreds of SIMs on one cell site with no voice traffic is a distinctive pattern. Ranges sourced that way tend to be flagged sooner, which shows up later as a delivery rate that falls away within weeks.

Also known as

  • sim box
  • gsm gateway
  • modem bank

Related terms