Know MTU size

[vallapaneni]

Hi,
I would like to know what is the negotiated MTU size in my app. I see that MTU negotiation happens between central and peripheral devices. On central device, I have my Qt app. Some of the received packets I have to re-assemble based on MTU size. Please guide how to know MTU size.

Rgds,
Venkat.

[debian]

https://en.wikipedia.org/wiki/Maximum_transmission_unit

or you search software way ?

[vallapaneni]

Hi,
I am looking how to know what is the negotiated MTU size in QT. Based on negotiated MTU size, I may have to assemble multiple packets to get the application layer packet. For assembling, I need to know what is the MTU size of the central device controlled by QT.

Rgds,
Venkat.

[jsulm]

@vallapaneni said in Know MTU size:

I may have to assemble multiple packets

But why? This is something TCP is already doing for you.

[vallapaneni]

Hi,
My ble peripheral device sends application layer packet by segmenting as per MTU size.For example, central device may send a request and peripheral response needs to be 56 bytes. In such case, if negotiated MTU size is 23, peripheral device sends them as 3 segmented packets. On the central device side, I need to assemble them and form 56b bytes payload.

Rgds,
Venkat.