One thing that this circular does is distinguish between algo orders and API orders. If the order rates are within a prescribed order-per-unit-time threshold, they won’t get tagged as algo even if they come from APIs. And algos need to be registered, not API orders. For most retail APIs, broker risk management rules already have these limits in place, so this shouldn’t be a problem.
Why? This is so only algos that are bypassing some RMS parameters need exchange registration while others (most retail ones) remain exempt, making it feasible for people to use APIs.
But ISPs also provide static IPs. Users may have to purchase one. This is a compromise to allow APIs while ensuring origin of orders is always known. Better than not allowing APIs. 