Ip Address Assignment; Nailed-Up Connection (Ppp); Nat; Metric - ZyXEL Communications P-660HN User Manual

Chapter 5 WAN Setup

5.5.4 IP Address Assignment

A static IP is a fixed IP that your ISP gives you. A dynamic IP is not fixed; the ISP assigns you
a different one each time. The Single User Account feature can be enabled or disabled if you
have either a dynamic or static IP. However the encapsulation method assigned influences
your choices for IP address and ENET ENCAP gateway.
IP Assignment with PPPoA or PPPoE Encapsulation
If you have a dynamic IP, then the IP Address and Gateway IP Address fields are not
applicable (N/A). If you have a static IP, then you only need to fill in the IP Address field and
not the Gateway IP Address field.
IP Assignment with RFC 1483 Encapsulation
In this case the IP address assignment must be static.
IP Assignment with ENET ENCAP Encapsulation
In this case you can have either a static or dynamic IP. For a static IP you must fill in all the IP
Address and Gateway IP Address fields as supplied by your ISP. However for a dynamic IP,
the ZyXEL Device acts as a DHCP client on the WAN port and so the IP Address and
Gateway IP Address fields are not applicable (N/A) as the DHCP server assigns them to the
ZyXEL Device.

5.5.5 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.

5.5.6 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.

5.6 Metric

The metric represents the "cost of transmission". A router determines the best route for
transmission by choosing a path with the lowest "cost". RIP routing uses hop count as the
measurement of cost, with a minimum of "1" for directly connected networks. The number
must be between "1" and "15"; a number greater than "15" means the link is down. The
smaller the number, the lower the "cost".
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P-660HN-Fx User's Guide