WR3000 4-Port Wireless DSL/Cable Router
®
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5.6 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 WR3000 Wireless Router supports both IGMP version 1 (IGMP-vl) and IGMP version 2
(IGMP-v2).
At start up, the WR3000 Wireless Router queries all directly connected networks to gather group
membership. After that, the WR3000 Wireless Router periodically updates this information. IP
multicasting can be enabled/disabled on the WR3000 Wireless Router LAN and/or WAN interfaces
in the Web Confi guration Utility (LAN; WAN). Select None to disable IP multicasting on these
interfaces.
5.7 Confi guring the LAN IP Screens
Click ADVANCED and then LAN to open the IP Screen.
This screen’s options are described on the next page.
Apply Reset
DHCP Setup
LAN TCP/IP
Windows Networking (NetBIOS over TCP/IP)
DHCP Server
IP Pool Starting Address
192.168.150.32
Pool Size
12
DNS Servers Assigned by DHCP Server
First DNS Server
Second DNS Server
Third DNS Server
From ISP
0.0.0.0
0.0.0.0
0.0.0.0
IP Address
IP Subnet Mask
Multicast
192.168.150.1
255.255.255.0
None
Allow between LAN and WAN
LAN
From ISP
From ISP
RIP Direction
RIP Version
Both
RIP-1
IP