[erlang-questions] IP packet manipulation within Erlang

[Chandru]

2010/1/7 Martti Kuparinen <martti.kuparinen@REDACTED>

> Hi,
>
> How suitable is Erlang for a small project where I'd like to
>
> - grab all incoming IP packets
> - perform some IP header manipulation
> - send out the modified packets
>
> I'm aware I need some kind of bpf/pcap driver to get the packets into
> Erlang (or does Erlang now have something in this front).
>
> Do you guys have any idea how fast this whole thing would be compared to
> doing same in normal userland C program? Or even compared to doing the
> manipulation within Linux kernel.
>

I attempted this a few years ago. I tried to write a linked in driver which
got packets from libipq [1]. That was painful. So I dumped the idea of using
erlang at all, and did it all in C which was pretty straightforward and
worked quite well. I didn't put any large load on it, but it was enough for
what I was doing at the time.

cheers
Chandru

[1] http://en.wikipedia.org/wiki/Libipq