First, if you are in the U.S., please contact your congresspeople about
H.R. 1542, which would make unlicenced Internet telephony a crime:
http://www.pulver.com/hr1542/
http://www.pulver.com/hr1542/illegal.html
http://www.pulver.com/hr1542/talkingpoints.html
I am useing a dynamic address to access the cable modem. But I cann't
establishe the eth0 interface. It looks I didn't receive a address.
The ethernet card is connected to a cable modem.
The second question is I recompiled the kernal which included Crystal
sound card. And it passed when system boot. But I cann't get any voice
service.
If your cable modem has a DHCP server, then it is probably also a NAT
box, which may prevent you from using a H.323 voice-over-IP application.
So you may have to disable the NAT features, and use a static IP address
on your Linux box (i.e., the address that was assigned to your cable modem
in the configuration paperwork that you were probably given), in which
case you might be able to use your Linux box as a private network DHCP
server and gateway if you have other DHCP clients. But depending on your
cable modem company and the VoIP software you chose, you may be able to
make it work with NAT.
These links will probably help you with the first question:
http://www.cablemodeminfo.com/LinuxCableModem.html
http://www.linuxdoc.org/HOWTO/mini/DHCP/
And here is a popular VoIP telephony program that supports RTP (RFC 1899)
and L.B.L. VAT protocols, but doesn't depend on H.323, so you might be
able to use it even if you are behind a NAT box (but maybe not if both
ends are behind different NAT boxes -- although there is probably some
trick to make that work, I can't think of what off the top of my head.)
http://www.fourmilab.ch/speakfree/unix/
http://www.germane-software.com/SpeakFreely/
If you achieve a static IP address, you may be able to use OpenH.323 and
interoperate with the huge number of H.323 clients:
http://www.openh323.org/code.html
http://www.openh323.org/h323_clients.html
Cheers,
James