P-660R/H-D Series User’s Guide

6.1.4.2 IP Assignment with RFC 1483 Encapsulation

In this case the IP Address Assignment must be static with the same requirements for the IP Address and ENET ENCAP Gateway fields as stated above.

6.1.4.3 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 ENET ENCAP Gateway fields as supplied by your ISP. However for a dynamic IP, the Prestige acts as a DHCP client on the WAN port and so the IP Address and ENET ENCAP Gateway fields are not applicable (N/A) as the DHCP server assigns them to the Prestige.

6.1.5 Nailed-Up Connection (PPP)

A nailed-up connection is a dial-up line where the connection is always up regardless of traffic demand. The Prestige does two things when you specify a nailed-up connection. The first is that idle timeout is disabled. The second is that the Prestige 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

6.1.6 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.

6.2 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".

The metric sets the priority for the Prestige’s routes to the Internet. If any two of the default routes have the same metric, the Prestige uses the following pre-defined priorities:

•Normal route: designated by the ISP (see Section 6.7 on page 75)

•Traffic-redirect route (see Section 6.8 on page 78)

•WAN-backup route, also called dial-backup (see Section 6.9 on page 79)

Chapter 6 WAN Setup

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