Optimizing DLE, and ATT MTU for specific data packet size

RE: Optimizing DLE, and ATT MTU for specific data packet size

Tai — Thu, 28 Sep 2023 05:40:10 GMT

Thanks for this information!

RE: Optimizing DLE, and ATT MTU for specific data packet size

Sigurd — Wed, 20 Sep 2023 09:16:01 GMT

[quote user="Tai Le"] Let say the data packet size is 40 bytes, using DLE size of 251 bytes and ATT MTU of 247 bytes, will it be more packets (multiple 40-byte data packets) needing to be sent for the same amount of data? I'm asking this as it may lower the throughput in this case.[/quote]

No, it will be a single 40 byte packet sent.

RE: Optimizing DLE, and ATT MTU for specific data packet size

Tai — Tue, 19 Sep 2023 16:50:13 GMT

Thanks Sigurd for this information!

Regarding the question 2, could you explain a little bit more about? Let say the data packet size is 40 bytes, using DLE size of 251 bytes and ATT MTU of 247 bytes, will it be more packets (multiple 40-byte data packets) needing to be sent for the same amount of data? I'm asking this as it may lower the throughput in this case.

RE: Optimizing DLE, and ATT MTU for specific data packet size

Sigurd — Tue, 19 Sep 2023 15:27:02 GMT

Hi!

[quote user=""]Does this matter to set optimal DLE and ATT MTU size for specific data packet size? like save power consumption or even increase throughput?[/quote]

Yes. If the ATT packet cannot fit in a single on-air packet, it will be split up into multiple on-air packets. By using DLE, you can set DLE to ATT packet size plus the header bytes. This will avoid fragmentation of the ATT packet into several on-air data packets.

[quote user=""]For data packet size greater than 23, with the use of DLE of 251 bytes and ATT MTU of 247 bytes, is it overkill?[/quote]

I don't see any downside to setting DLE and ATT MTU to these values. Even if your application don't actually need this high values, the peer device you are connected to might benefit from these higher values.