ZyXEL p-660r-t1 v2 Manual Do Utilizador

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P-660R-Tx v2 Series User’s Guide
Chapter 3 Wizard Setup
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3.2.1.4  Private IP Addresses
Every machine on the Internet must have a unique address. If your networks are isolated from 
the Internet, for example, only between your two branch offices, you can assign any IP 
addresses to the hosts without problems. However, the Internet Assigned Numbers Authority 
(IANA) has reserved the following three blocks of IP addresses specifically for private 
networks:
• 10.0.0.0     —  10.255.255.255
• 172.16.0.0   —  172.31.255.255
• 192.168.0.0  —  192.168.255.255
You can obtain your IP address from the IANA, from an ISP or it can be assigned from a 
private network. If you belong to a small organization and your Internet access is through an 
ISP, the ISP can provide you with the Internet addresses for your local networks. On the other 
hand, if you are part of a much larger organization, you should consult your network 
administrator for the appropriate IP addresses.
Note: Regardless of your particular situation, do not create an arbitrary IP address; 
always follow the guidelines above. For more information on address 
assignment, please refer to RFC 1597, Address Allocation for Private Internets 
and RFC 1466, Guidelines for Management of IP Address Space.
3.2.2  Nailed-Up Connection (PPP)
A nailed-up connection is a dial-up line where the connection is always up regardless of traffic 
demand. The ZyXEL Device does two things when you specify a nailed-up connection. The 
first is that idle timeout is disabled. The second is that the ZyXEL Device will try to bring up 
the connection when turned on and whenever the connection is down. A nailed-up connection 
can be very expensive for obvious reasons. 
Do not specify a nailed-up connection unless your telephone company offers flat-rate service 
or you need a constant connection and the cost is of no concern
3.2.3  NAT
NAT (Network Address Translation - NAT, RFC 1631) is the translation of the IP address of a 
host in a packet, for example, the source address of an outgoing packet, used within one 
network to a different IP address known within another network.
3.2.4  Internet Access Wizard Setup: Second Screen
The second wizard screen varies depending on what mode and encapsulation type you use. All 
screens shown are with routing mode. Configure the fields and click Next to continue.