ZyXEL Communications Prestige 2802HW(L)-IX Support Notes page 5

How are voice quality normally rated?......................................................134
What is codec? ...........................................................................................134
What is the relation of codec and VoIP? ...................................................135
What codec does Prestige support?............................................................135
Which codec should I choose?...................................................................135
What do I need in order to use SIP? ..........................................................135
Unable to register with the SIP server?......................................................136
I can register but can not establish a call?..................................................136
I can make a call but the voice only goes one way not bothway? .............136
I can receive a call but the voice only goes one way not bothway? ..........136
If all the about have been tried, but register still fail what should I do?....136
I suspect there is a hardware problem with my Prestige what should I do?137
Firewall FAQ .....................................................................................................137
What is a network firewall? .......................................................................137
What makes Prestige firewall secure? .......................................................137
What are the basic types of firewalls? .......................................................137
What kind of firewall is the Prestige?........................................................138
Why do you need a firewall when your router has packet filtering and
NAT built-in?.............................................................................................138
What is Denials of Service (DoS)attack?...................................................139
What is Ping of Death attack?....................................................................139
What is Teardrop attack? ...........................................................................139
What is SYN Flood attack?........................................................................139
What is LAND attack?...............................................................................140
What is Brute-force attack? .......................................................................140
What is IP Spoofing attack?.......................................................................140
What are the default ACL firewall rules in Prestige? ................................140
How can I protect against IP spoofing attacks? .........................................141
Content Filter FAQ ............................................................................................142
IPSec FAQ .........................................................................................................142
What is VPN? ............................................................................................142
Why do I need VPN? .................................................................................142
What are most common VPN protocols?...................................................143
What is PPTP? ...........................................................................................143
What is L2TP? ...........................................................................................143
What is IPSec? ...........................................................................................143
What secure protocols does IPSec support? ..............................................144
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Prestige 2802HW(L)-Ix Support Notes
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