Hey

We are trying to determine the best strategy for implementing a high speed
hard real-time ethernet protocol (EtherCAT master). We are considering
using io-pkt package filtering as the method for sending and receiving raw
EtherCAT packages (Ethernet packages with ethertype EtherCAT) which needs
to be transmitted at a higher frame rate than available from commercial
vendors as source code for QNX. 

Is this possible (and reccomendable) using package filtering (or
alternatively bpf) under io-pkt, or should we go for a more "direct"
autonomous control of the standard NIC interface in order to reach sub
200us package frame rate?

The core networking documentation for io-pkt states that the ip-part is
tightly compiled into io-pkt. Does this mean that transmitting raw
EtherCAT frames without IP src and dst addresses will be impossible for us
using io-pkt?

The io-pkt is proberly not build for real-time communications, so maybe it is an argument for writing our own stack, and
 not use the io-pkt.