ZyXEL Communications P-2302HWUDL-P1 Support Notes page 5

What DDNS servers does the ZyXEL Device support? ............................ 151
What is DDNS wildcard? ........................................................................... 151
Does the ZyXEL Device support DDNS wildcard? .................................. 151
Can the ZyXEL Device SUA handle IPsec packets sent by the VPN
gateway behind ZyXEL Device? ............................................................... 151
How do I setup my ZyXEL Device for routing IPsec packets over SUA? 152
VoIP FAQ ...........................................................................................................152
What is Voice over IP? ............................................................................... 152
How does Voice over IP work? .................................................................. 152
Why use VoIP? ........................................................................................... 152
What is the relationship between codec and VoIP? ................................... 153
What advantage does Voice over IP can provide? ..................................... 153
What is the difference between H.323 and SIP? ........................................ 153
Can H.323 and SIP interoperate with one another? ................................... 153
What is voice quality? ................................................................................ 153
How are voice quality normally rated? ...................................................... 153
What is codec? ........................................................................................... 154
What is the relation of codec and VoIP? .................................................... 154
What codec does the ZyXEL Device support? .......................................... 154
Which codec should I choose? ................................................................... 154
What do I need in order to use SIP? .......................................................... 154
Unable to register with the SIP server? ...................................................... 155
I can register but can not establish a call? .................................................. 155
I can make a call but the voice only goes one way not in both ways? ....... 155
I can receive a call but the voice only goes one way not bothway? .......... 155
If all the about have been tried, but register still fail what should I do? .... 155
I suspect there is a hardware problem with my ZyXEL Device what should
I do? ........................................................................................................... 156
Trouble Shooting ...................................................................................................... 156
Unable to Get WAN IP from ISP .......................................................................156
Using Embedded Packet Trace ..........................................................................159
Debug PPPoE Connection .................................................................................174
CLI Command List .................................................................................................. 185
All contents Copyright  2007 ZyXEL Communications Corporation.
P2302HWUDL-P1 Support Notes
5