You could perhaps use libnet to simplify the your life a little bit: http://www.packetfactory.net/libnet/ Alternatively, you could utilize the Click framework for this. It's actually quite easy to build a fully standards-compliant TCP/IP stack with Click. Modifying it for your special purposes likely wouldn't be all that difficult. Click actually has their own mailing list, which I've found quite useful: https://pdos.csail.mit.edu/mailman/listinfo/click -Adam On Wed, 8 Aug 2007 09:22:23 +0100, "Brian Candler" <B.Candler@xxxxxxxxx> said: > What I'm thinking is that it may be possible using raw sockets to send > packets, and libpcap to receive the responses. That means that ARP would > be > handled entirely in userland. However, in order to telnet the router, I > would also need a complete TCP stack which runs entirely in userland. Is > such a thing publically available? (*) - To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html