Set-set (secure electronic transaction) is a system for ensuring the security of financial transactions on the internet. it was supported initially by mastercard, visa, microsoft, netscape, and others. with set, a user is given an electronic wallet (digital certificate) and a transaction is conducted and verified using a combination of digital certificates and digital signatures among the purchaser, a merchant, and the purchasers bank in a way that ensures privacy and confidentiality. set makes use of netscapes secure sockets layer (ssl (secure sockets layer)), microsofts secure transaction technology (stt), and terisa systems secure hypertext transfer protocol (s-http). set uses some but not all aspects of a public key infrastructure (public key infrastructure). tls, ssl and shttp could all be used for this, but set is specific to the financial services industry.