(I posted this note on http://www.voip-info.org/wiki-ZyXEL+P2000W+configuration too) I tried to put together comments that were asked for on the P2000W. These configs seem to work fine for a ZyXEL P2000W, thanks to Giles Scott for getting me started with it. DTMF keys work fine and are "read" correctly by Asterisk. It's important that you upgrade your phone to a modern version of the firmware - it didn't work much with the WJ.00.07 that was preinstalled on my terminal, while it works with WJ.00.0c See: http://www2.studerus.ch/support.cfm?action=news&lang=d http://www.nikotel.net/firmware/zyxel/p2000w/P2000W_WJ000E_Standard.zip In this example, my phone has number 898 and 10.10.3.5 is Asterisk. Cheers l. sip.conf [898] type=friend username=phone secret=---mypassword--- host=dynamic canreinvite=no context=sip disallow=all allow=alaw dtmfmode=rfc2833 On the telephone web interface: Zyxel config SIP/outbound Proxy config Proxy IP:10.10.3.5 Proxy port = 5060 SIP Config SIP URI: sip: 898 @ 10.10.3.5 : 5060 Expire time: 300 Registrar username: 895 Registrar password: ---mypassword--- DSP setting Default Voice codec G.729 8k DTMF relay: outband -- Creato con M2, il rivoluzionario client e-mail di Opera: http://www.opera.com/m2/