P312 Broadband Security Gateway

The subnet mask specifies the network number portion of an IP address. Your Prestige 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 Prestige unless you are instructed to do otherwise.

3.1.3 Private IP Addresses

Every machine on the Internet must have a unique address. If your networks are isolated from the Internet, e.g., only between your two branch offices, you can assign any IP addresses to the hosts without problems. However, the Internet Assigned Numbers Authority (IANA) has reserved the following three blocks of IP addresses specifically for private networks:

10.0.0.0- 10.255.255.255

172.16.0.0- 172.31.255.255

192.168.0.0 - 192.168.255.255

You can obtain your IP address from the IANA, from an ISP, or assigned from a private network. If you belong to a small organization and your Internet access is through an ISP, the ISP can provide you with the Internet addresses for your local networks. On the other hand, if you are part of a much larger organization, you should consult your network administrator for the appropriate IP addresses.

Regardless of your particular situation, do not create an arbitrary IP address; always follow the guidelines above. For more information on address assignment, please refer to RFC 1597, Address Allocation for Private Internets and RFC 1466, Guidelines for Management of IP Address Space.

3.1.4 RIP Setup

RIP (Routing Information Protocol, RFC1058 and RFC 1389) allows a router to exchange routing information with other routers. The RIP Direction field controls the sending and receiving of RIP packets. When set to Both or Out Only, the Prestige 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.

The Version field controls the format and the broadcasting method of the RIP packets that the Prestige sends (it recognizes both formats when receiving). RIP-1is universally supported; but RIP-2carries more information. RIP-1is probably adequate for most networks, unless you have an unusual network topology. Both RIP-2Band RIP-2Msends the routing data in RIP-2 format; the difference being that RIP-2Buses subnet broadcasting while RIP-2Muses multicasting. Multicasting can reduce the load on non-router machines since they generally do not listen to the RIP multicast address and so will not receive the RIP packets. However, if one router uses multicasting, then all routers on your network must use multicasting, also.

By default, RIP direction is set to Both and the Version set to RIP-1.

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Internet Access

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ZyXEL Communications P-312 manual Private IP Addresses, RIP Setup