[derefr]

Does Germany have exactly one financial interchange network?

Living in Canada, I tend to notice a wide variability in the response times of ATMs to withdrawal requests (i.e. the time between when you finalize the transaction request, and when it spins up the bill spitter) and I think the one factor I've noticed it coming down to is the number of interchange networks marked as being supported on the side of the machine.

The ones that just do Interac (the Canadian interbank debit-transaction network) are quite quick; the ones that do Interac and PLUS or Cirrus are slower; the ones that add support for cash advances on plain credit cards by supporting individual CC companies (Visa, AMEX) are slowest of all.

So, maybe it's not the number of applications on the card, per se, but rather the number of applications supported by the terminal, with some sort of O(N^2) interaction between them?

[germanier]

The POS terminals I talk about usually support at least MasterCard, Visa, Maestro, Vpay, and the German scheme Girocard (which in reality are multiple networks in its own). Some even more and they are still much faster than either using the same card in the US or using a US-issued card in the US. I'm honestly quite baffled as to why. I haven't tried a US card in a German terminal yet and neither looked closely at ATM speeds.