ZyXEL Communications HS100/HS100W manual Any IP, Multicast

HomeSafe User’s Guide

packets. When set to Both or Out Only, the HomeSafe 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 HomeSafe sends (it recognizes both formats when receiving). RIP-1is universally supported; but RIP-2carries more information. RIP-1 is probably adequate for most networks, unless you have an unusual network topology.

Both RIP-2Band RIP-2Msend 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 RIP Version to RIP-1.

5.3.4 Multicast

Traditionally, IP packets are transmitted in one of either two ways - Unicast (1 sender - 1 recipient) or Broadcast (1 sender - everybody on the network). Multicast delivers IP packets to a group of hosts on the network - not everybody and not just 1.

IGMP (Internet Group Multicast Protocol) is a network-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 information about interoperability between IGMP version 2 and version 1, please see sections 4 and 5 of RFC 2236. The class D IP address is used to identify host groups and can be in the range 224.0.0.0 to 239.255.255.255. The address 224.0.0.0 is not assigned to any group and is used by IP multicast computers. The address 224.0.0.1 is used for query messages and is assigned to the permanent group of all IP hosts (including gateways). All hosts must join the 224.0.0.1 group in order to participate in IGMP. The address 224.0.0.2 is assigned to the multicast routers group.

The HomeSafe supports both IGMP version 1 (IGMP-v1) and IGMP version 2 (IGMP-v2). At start up, the HomeSafe queries all directly connected networks to gather group membership. After that, the HomeSafe periodically updates this information. IP multicasting can be enabled/disabled on the HomeSafe LAN and/or WAN interfaces in the web configurator (LAN; WAN). Select None to disable IP multicasting on these interfaces.

5.4Any IP

Traditionally, you must set the IP addresses and the subnet masks of a computer and the HomeSafe to be in the same subnet to allow the computer to access the Internet (through the HomeSafe). In cases where your computer is required to use a static IP address in another network, you may need to manually configure the network settings of the computer every time you want to access the Internet via the HomeSafe.

With the Any IP feature and NAT enabled, the HomeSafe allows a computer to access the Internet without changing the network settings (such as IP address and subnet mask) of the computer, when the IP addresses of the computer and the HomeSafe are not in the same subnet. Whether a computer is set to use a dynamic or static (fixed) IP address, you can simply connect the computer to the HomeSafe and access the Internet.

The following figure depicts a scenario where a computer is set to use a static private IP address in the corporate environment. In a residential house where a HomeSafe is installed, you can still

5-2 LAN Screens