Справочник Пользователя для Netopia PN Series

Observe the following guidelines when using Network Address 
Translation.

■

The router can export just one local IP address per TCP port, so 
you can have just one machine available for a given service, 
such as one FTP server. However, some services, such as Web 
servers (www-http servers), allow you to change the TCP port 
on both the server and client. With two different TCP ports 
exported, you can have Web servers on two different IP hosts.

■

Associate your primary Domain Name Server (DNS) with 
whichever profile is more accessible.  If neither profile is 
dial-on-demand, you may associate a secondary DNS with the 
other profile.

You can enable Network Address Translation on one connection 
profile, disable it on another, and use the two profiles simulta-
neously.  The profiles might have the following attributes:

■

A profile with Network Address Translation disabled connects to 
your branch or main office.  Your company network 
administrator has assigned you a local IP address range that is 
consistent with the address space assigned to your company 
so that you seamlessly integrate when connected.  The remote 
IP address and mask for this profile define only the company’s 
address space, so that the only IP traffic you send over this 
connection is for hosts and servers within your company.

■

A Network Address Translation profile connects to the Internet 
via an ISP.  Even though the ISP assigns you a dynamic address 
each time you connect, there will be no address space conflict, 
since Network Address Translation hides the corporate address 
you use locally.  You enter the ISP’s remote IP address as your 
default IP gateway so that any IP traffic not intended for your 
corporate intranet will be directed to the ISP.