We have an application where response time is critical, and we are trying to minimize the time from advertising to an active channel sounding session.
What we have already optimized:
- Connection interval set to 7.5 ms
- Advertising interval reduced to 100 ms (can't go lower to remain within power constraints)
- Skip GATT discovery by hard-coding the GATT handles
- Bonding enabled to reduce secure connection setup time
This brings us down to around ~450 ms.
Now we are looking at what else we can do, and hope you can clarify what's possible.
- CS config/capabilities exchange takes ~100 ms.
- Our understanding is that per BLE specification, this can be avoided by pre-storing a known configuration on both sides.
- Does Noridc stack support or plan to support this?
- MTU exchange takes ~37 ms.
- Default MTU size is 23 and we must increase it for faster data exchange between reflector and initiator.
- Is there any way to hard-code the MTU size beforehand?
- CS security (bt_le_cs_security_enable) takes ~30 ms
- Is there anything we can do to reduce this? E.g. piggy-backing on the existing secure connection, skipping DRBG?
