ZyWALL 2 and ZyWALL 2WE

Table 7-2 Private IP Address Ranges

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 have it assigned by 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.

7.4.4RIP 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 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.

The Version field controls the format and the broadcasting method of the RIP packets that the ZyWALL 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.

7.4.5IP Multicast

Traditionally, IP packets are transmitted in one of either two ways - Unicast (one sender — one recipient) or Broadcast (one sender — everybody on the network). Multicast delivers IP packets to a group of hosts on the network - not everybody and not just one.

IGMP (Internet Group Multicast Protocol) is a session-layer protocol used to establish membership in a multicast group - it is not used to carry user data. IGMP version 2 (RFC 2236) is an improvement over version 1 (RFC 1112) but IGMP version 1 is still in wide use. If you would like to read more detailed

7-4

LAN Setup