Oh. You should use JEP-0066:Out of Band Data. If you still want "hack" it, I believe, you can skip step 4.8, go 4.9 directly. I presume you open the host before the step 4.5. Because Target already open socket with the Host Target choosed. You can set Activation, the Target should be start to read data, then you can send data. Good Luck Zhong Li