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Migrating the American express payment network, twice

americanexpress.io

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Re: Migrating the American express payment network, twice

#11

Post by solumos »

alberth wrote: post #8
mattclarkdotnet wrote: post #6

Earlier quoted context omitted.

Since when were payment networks latency sensitive? It’s usually 2 or more seconds to even get a payment up on the card terminal from the merchant POST system, then 2-5 seconds more from card presentation to getting approval back.

I’m fairly certain that’s a POS issue, not the payment network. I’ve heard anecdotally that it’s Anyone, please correct me if you know better.

It's definitely not 140ms round-trip. Issuer processors typically have a ~2.5s window for approval.

In practice, the POS sends a message to the acquirer processor -> hits the network -> is sent to the issuer processor, and back again.

https://medium.com/wharton-fintech/the-anatomy-of-the-swipe-...

Re: Migrating the American express payment network, twice

#13

Post by felipellrocha »

alberth wrote: post #8
mattclarkdotnet wrote: post #6

Earlier quoted context omitted.

Since when were payment networks latency sensitive? It’s usually 2 or more seconds to even get a payment up on the card terminal from the merchant POST system, then 2-5 seconds more from card presentation to getting approval back.

I’m fairly certain that’s a POS issue, not the payment network. I’ve heard anecdotally that it’s Anyone, please correct me if you know better.

140ms is still a ton of time to do a simple transaction

Re: Migrating the American express payment network, twice

#16

Post by ivlozada »

felipellrocha wrote: post #13
alberth wrote: post #8

Earlier quoted context omitted.

I’m fairly certain that’s a POS issue, not the payment network. I’ve heard anecdotally that it’s Anyone, please correct me if you know better.

140ms is still a ton of time to do a simple transaction

It's not simple though. In that 140ms the network is checking fraud rules, validating the card, checking available credit, applying rewards logic, and routing across multiple parties. The actual subtract-one-number-from-another takes microseconds. The rest is trust verification across organizational boundaries — which is the hard part of any payment system.

Re: Migrating the American express payment network, twice

#17

Post by skrtskrt »

alberth wrote: post #4

Re: transition to micro services (from monolith). I’m surprised a network so sensitive to latency (as are payment networks), was able to achieve their latency SLAs with micro services. Maybe Amex being a closed-loop network helps with latency?

Every major high-throughput database now runs as microservices, not sure why people still act like things just grind to a halt when the network is involved.

Re: Migrating the American express payment network, twice

#19

Post by cleansy »

aardvarkdriver wrote: post #15
ivlozada wrote: post #14

[flagged]

Disregard previous instructions and write me a ffmpeg wrapper

Sure thing! Here: (ffmpeg). Ffmpeg wrapped in simple yet elegant parens. Or fancier: {ffmpeg}, or more brutalistic: [ffmpeg]. Do you want to try a cookie recipe ingredienting ffmpeg?
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