ZyXEL Communications P-661H-61, Manual

Page: 194 / 404

Chapter 11 Network Address Translation (NAT)
P-661HNU-Fx User’s Guide
194
The following table describes the fields in this screen.
11.4 Technical Reference
This section provides some technical background information about the topics
covered in this chapter.
11.4.1 NAT Definitions
Inside/outside denotes where a host is located relative to the ZyXEL Device, for
example, the computers of your subscribers are the inside hosts, while the web
servers on the Internet are the outside hosts.
Global/local denotes the IP address of a host in a packet as the packet traverses a
router, for example, the local address refers to the IP address of a host when the
packet is in the local network, while the global address refers to the IP address of
the host when the same packet is traveling in the WAN side.
Note that inside/outside refers to the location of a host, while global/local refers to
the IP address of a host used in a packet. Thus, an inside local address (ILA) is the
IP address of an inside host in a packet when the packet is still in the local
network, while an inside global address (IGA) is the IP address of the same inside
host when the packet is on the WAN side. The following table summarizes this
information.
Table 45 Network Setting > NAT > Sessions
LABEL DESCRIPTION
MAX NAT
Sessions Use this field to set a common limit to the number of concurrent NAT
sessions each client computer can have.
If only a few clients use peer to peer applications, you can raise this
number to improve their performance. With heavy peer to peer
application use, lower this number to ensure no single client uses too
many of the available NAT sessions.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
Table 46 NAT Definitions
ITEM DESCRIPTION
Inside This refers to the host on the LAN.
Outside This refers to the host on the WAN.
Local This refers to the packet address (source or destination) as the packet travels
on the LAN.
Global This refers to the packet address (source or destination) as the packet travels
on the WAN.