> For the complete documentation index, see [llms.txt](https://docs.casa.io/wealth-security-protocol/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.casa.io/wealth-security-protocol/chosen-features/heterogeneous-hardware-and-software.md).

# Heterogeneous Hardware and Software

In a typical 3-of-5 setup, we use **at leas three different hardware/software platforms** at one time - such as Trezor, Ledger, and a mobile phone (iOS or Android). Neither software nor hardware wallets are perfect. From time to time a vulnerability is discovered in one brand. Relying on multiple brands and types of wallets prevents a vulnerability in one brand from compromising the overall storage system. 

This also protects against supply chain attacks. If a malicious actor were to infiltrate and tamper with the devices produced by any one supplier, it would not be enough to compromise our clients' funds.