Hello developers, what is the best way to find out that a given core-frequency isn't sufficient for carrying 6LoWPAN protocol? I guess if the cpu-frequency is too low it just won't work ....no hint from the OS side - is this true? Best regards, Bernhard
Hello Bernhard,
are you worrying that the MCU might be too slow in processing 6LoWPAN packets to get a 802.15.4 stream with 250 kbit/s? Thought it could be interesting to give some rough numbers:
I did measurements with an IPv6 network stack using RIOT conn sockets, UDP, IPv6, 6LoWPAN, NOMAC, and a link layer dummy that processes the 802.15.4 header but without device driver code. On an Atmel samr21-xpro with 48MHz MCU frequency, processing/stack-tracing takes *approximately* 2.5ms for a UDP packet with 1000 Bytes payload when hammering the stack. That leads to a theoretical throughput of about 3,2Mbit/s which is more than 10 times the radio data rate.
I would doubt that you'll actually reach this upper bound in a real world scenario although this is just my personal opinion without the evaluation of concrete numbers. I've no idea what's the best way to go here. But IMO the network stack would need to know about it's performance then, right?
BTW: Is the question about networking modules in the process list still an open topic for you?
Best Peter