>A PSP packet starts with the original IP header, followed by a UDP header on a prespecified destination port, followed by a PSP header containing the PSP infor

>A PSP packet starts with the original IP header, followed by a UDP header on a prespecified destination port, followed by a PSP header containing the PSP information, followed by the original TCP/UDP packet So it looks like the inner data can be either TCP or UDP. So you have the option of making it reliable or not.