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by germanier 3281 days ago
What I don't understand is that even when using a German card with multiple applications, online authentication, and online authorisation[0] it's quite fast in Germany – much faster than comparable or even simpler transactions in the US. On the other hand, the very same card is processed even faster when used in Sweden.

The difference is probably faster data connections and more efficient protocol implementations, I would think.

[0]: For some reason receipts here contain quite a lot of information on what happens behind the scenes if you know how to read it. I hope this link keeps working, it contains exercepts of receipts merchants give you here: http://docplayer.org/storage/33/16568026/1498495227/GbAKHYXN... With that information you can e.g. see which steps were perfomed offline.

2 comments

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?

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.
Your link gives a 403, could you re-upload it somewhere else?
I made a screenshot of the most interesting example: http://imgur.com/ye5MJcH This is what they print out for the international schemes. On the left is what the customer gets (sometimes directly on the receipt, sometimes on an extra piece of paper), the right one is for the merchant (some only save it electronically now). Some terminals show less info but much of it is almost always present, something which I haven't seen much internationally in that level of detail.
You can decipher some of the fields printed on the receipt using https://tvr-decoder.appspot.com. The acronyms are from the EMV specs (https://www.emvco.com/specifications.aspx?id=223, probably book 3)

Eg. TVR: 0000008000 (Byte 4 Bit 8) Transaction exceeds floor limit

Floor limit being the $/EUR/whatever amount that could be approved offline.

The 2 in the diagram appears to be pointing at a cleartext credit card number.