[user5994461]

For comparison, when I received the RFP for the Italian and the British (gov uk verify) national authentication systems.

The numbers that were asked for were 12k/auth per second during peak time for the Italians.

The British wasn't clear but it hinted at 0.1% of user authenticating per second, which is about the same range. (The numbers of users itself was not defined, it depends on who would join the program).

SLA: 1500 ms for the account verification. 150 ms for most operations. (Some more time when requesting optional attributes like name/address/phone)

If this interests you, I've published a few numbers I got from preliminary testing (to determine whether we could answer the RFP or not): https://thehftguy.com/2015/10/23/10-millions-users-accounts-...