I've given the website a bit of an update so I can more easily post articles. I have maintained the existing content which was predominantly about Volkswagen/Audi group communication protocols and my ECU tuning software. Here is a quick overview.
CAN allows for data packets with a payload of up to 8 bytes, to send messages longer than 8 bytes it is necessary to use a transport protocol. The OBD-II specification for example makes use of ISO-TP (ISO 15765-2). Volkswagen however uses it's own transport protocol in its vehicles, known as VW TP 2.0.