ZyXEL Communications 70 Series User Manual

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ZyWALL 5/35/70 Series User’s Guide
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Chapter 5 LAN Screens
These parameters should work for the majority of installations. If your ISP gives you explicit 
DNS server address(es), read the embedded web configurator help regarding what fields need 
to be configured.
5.3.2  IP Address and Subnet Mask
Similar to the way houses on a street share a common street name, so too do computers on a 
LAN share one common network number.
Where you obtain your network number depends on your particular situation. If the ISP or 
your network administrator assigns you a block of registered IP addresses, follow their 
instructions in selecting the IP addresses and the subnet mask.
If the ISP did not explicitly give you an IP network number, then most likely you have a single 
user account and the ISP will assign you a dynamic IP address when the connection is 
established. If this is the case, it is recommended that you select a network number from 
192.168.0.0 to 192.168.255.0 and you must enable the Network Address Translation (NAT) 
feature of the ZyWALL. The Internet Assigned Number Authority (IANA) reserved this block 
of addresses specifically for private use; please do not use any other number unless you are 
told otherwise. Let's say you select 192.168.1.0 as the network number; which covers 254 
individual addresses, from 192.168.1.1 to 192.168.1.254 (zero and 255 are reserved). In other 
words, the first three numbers specify the network number while the last number identifies an 
individual computer on that network.
Once you have decided on the network number, pick an IP address that is easy to remember, 
for instance, 192.168.1.1, for your ZyWALL, but make sure that no other device on your 
network is using that IP address.
The subnet mask specifies the network number portion of an IP address. Your ZyWALL will 
compute the subnet mask automatically based on the IP address that you entered. You don't 
need to change the subnet mask computed by the ZyWALL unless you are instructed to do 
otherwise.
5.3.3  RIP Setup
RIP (Routing Information Protocol, RFC 1058 and RFC 1389) allows a router to exchange 
routing information with other routers. RIP Direction controls the sending and receiving of 
RIP packets. When set to Both or Out Only, the ZyWALL will broadcast its routing table 
periodically. When set to Both or In Only, it will incorporate the RIP information that it 
receives; when set to None, it will not send any RIP packets and will ignore any RIP packets 
received.  
RIP Version controls the format and the broadcasting method of the RIP packets that the 
ZyWALL sends (it recognizes both formats when receiving). RIP-1 is universally supported; 
but RIP-2 carries more information. RIP-1 is probably adequate for most networks, unless you 
have an unusual network topology.