[tripue]

We faced the same problem at Zenly and had to build our own anti-spam strategies to prevent it. We used multiple providers to improve our conversion rate and reduce cost. We are now building this as a service https://www.ding.live/ and are seeing huge improvements for our first customers in term of cost savings and conversion rate. Feel free to reach out if it could be any interest to you [e-mail].

[fasteo]

There is no way you are using high-quality routes for the "lowest price"[1] (just checked some random countries I have direct experience with)

Spain 0.0094 Italy 0.0159 Germany 0.0198

Most likely, your upstream providers are using SIM farms

High quality routes - either direct operator connections or 1-hop - will have these aprox pricing

Spain ~0.021-0.023 Italy ~0.026-0.030 Germany ~0.06-0.07

[1] https://dinglive.notion.site/SMS-e03051265199429cb36aed17bac...

[tripue]

We use a combinaison of route that are are evaluated in real-time for their cost to conversion ratio. Our customers have the option to choose only « direct routes » if needed but those strategies are use at scale by players like Facebook, TikTok or Google we’re just making sure our customer have all the options, visibility and control on their conversion rate/price tradeoff. Another strategy that allows to lower cost significantly is the use of alternative channel when available and competitive : Google RBM, WhatsApp, Viber, line.. Last but not least we don’t do any margin on the sms price so we bill back exactly what we pay for and negotiate with aggregated volumes.

[fasteo]

>>> evaluated in real-time for their cost to conversion ratio

We tried that in the past, but our business (mostly OTP for banks) do not allow any margin of error at all. The thing is that we would get positive delivery reports which were fake.

We also tried some 3rd party testing tools (Testelium[1], TestMySMS[2], etc) but again, our hacky upstream providers were ahead of us and they would put those test number in white-list so that everything would look just fine when testing.

At the end, we settled for direct or 1-hop connection. Margins are tight, but this is the only way to offer a high quality service.

Of course, YMMV

[1] https://testelium.com/

[2] https://www.testmysms.com/

[toast0]

> We tried that in the past, but our business (mostly OTP for banks) do not allow any margin of error at all. The thing is that we would get positive delivery reports which were fake.

SMS delivery reports have a limited connection to reality (but IMHO, requesting them seems to improve delivery rates), but you can (and should) measure conversion and route based on that.

If you have no margin for error, you might prefer directs, but when the direct route stops working, you need an alternative.

[tripue]

Yes, it's hard to rely on delivery report, we don't rely on this to evaluate the conversion on a given route.

Thanks for sharing the testing tools super helpful !