BLE peripheral throughput limit

Question

We are developing a BLE sensor Peripheral to work with an iPad, that requires the following throughput of data on the BLE notification characteristic (no acknowledge) using

Answer 1

We use TI 2540 (BLE stack version 1.3.2) succesfully with iPad/iPod/iPhone (iOS 6.x and 7.x). We currently send 75 notifications of 20 bytes per second => 1500 bytes/second. But I have tried to send 125 notifications and that worked as well.

Of course the more you send the greater likelihood of loosing data, e.g., less time to resend a NACK'ed message.

I have experienced that iOS' BLE stack may enter a mode where it begins to NACK messages continuously. If this happens you will loose a lot of messages. I have reported an error to Apple about this. (This problem seems to have been fixed in iOS 7.1.beta3/4.)

I currently have:

// Minimum connection interval (units of 1.25ms, 80=100ms) if automatic parameter update request is enabled
#define DEFAULT_DESIRED_MIN_CONN_INTERVAL     10

// Maximum connection interval (units of 1.25ms, 800=1000ms) if automatic parameter update request is enabled
#define DEFAULT_DESIRED_MAX_CONN_INTERVAL     20

Yes, it doesn't conform with Apple's guidelines. But I believe they can be relaxed in our case.

UPDATE: I have also tried to use an iDevice as peripheral, i.e., BTLE between two iDevices. Here I have sent 150 messages per second without any problems. Check the code here.