These existing systems include the Euro Banking Association's Euro 1 system, the systems used by international credit cards (VISA, Eurocard, Mastercard) and systems established between groups of banks (e.g. Eurogiro, Unico, S-Interpay).
Hier seien u.a. das Euro-1-System des Euro-Bankenverbands, die internationalen Kreditkartensysteme (VISA, Eurocard, Mastercard) und zwischen Bankengruppen entstandene Überweisungsabwicklungssysteme (e.g. Eurogiro, Unico, S-Interpay) genannt.