Seneca Z-PASS1, Руководство пользователя

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USER MANUAL – Z-PASS1/Z-PASS2
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14 Router
As already told before, “Router” functionality routes packets between the LAN (Ethernet) interface and the
WAN (Mobile Network) interface; so, this functionality specially makes sense when a PPP connection is
active, which needs the availability of a 3G modem (always true for Z-PASS2, true for Z-PASS1 when
connected to Seneca Z-MODEM-3G modem).
More specifically, an important feature of the Router is what is known as “IP forwarding”; this means that
when Z-PASS receives a packet not targeted for it, it does not discard the packet but forwards it to its actual
destination; when a packet is routed from the LAN to the WAN, Z-PASS also performs what is known as “IP
masquerading”, meaning that the original source IP address is replaced with the IP address of the WAN
(PPP) interface.
Another important feature is the availability of a DNS server/forwarder, which can resolve names either by
itself or querying the external configured DNS server.
Also, a DHCP server is available which assigns IP addresses to clients connected on the Z-PASS LAN; here,
you can configure the range of addresses used by the server and the lease time.
There is also the possibility to define up to five “Port Forwarding” rules or “Virtual Servers”; using these
rules, you can, for example, redirect packets received from a TCP or UDP port to another Z-PASS port or to
another machine, with a different IP address, on the same or another port.
As an alternative to using “Port Forwarding” rules, Router + VPN functionalities allow the use of local
addresses, as shown in the previous chapter; in the router configuration, a flag is given to enable this
feature.
A detailed description of the Router configuration can be found in 18.8 paragraph.