The cost impact is then lowered by spreading it equitably across the product line. Button is needed to protect one or all of the products. Buttons yielded free protection for the additional two options. However, this forces the software vendor to rely on the integrity of the exact same security code, assigned by the security device provider, for the base product and the options. While this costs the same as an i Button approach, it compromises security because the same code is used for all products.
Buttons offer higher security for no additional cost.
In situations where only a single i Button per option is more logistically practical, multiple i Buttons can multidrop, that is, connect together. This leverages the electronics from one holder across all i Buttons, saving the cost of purchasing additional holders for the other applications. The multidrop capability of the i Buttons is made possible because each i Button contains a unique 64 bit identification number that is unalterable and guaranteed to be unique. Software routines can identify strings of i Buttons connected together using the 1-wire protocol by their unique identification numbers. A benefit is that users can insert the i Buttons into i Button ports in any order.