Using IP Multicast
Traditionally, IP packets are transmitted in two ways - unicast or broadcast.
Multicast is a third way to deliver IP packets to a group of hosts. Host
groups are identified by class D IP addresses, i.e., those with "1110"
as their higher-order bits. In dotted decimal notation, host group addresses
range from 224.0.0.0 to 239.255.255.255. Among them, 224.0.0.1 is assigned
to the permanent IP hosts group, and 224.0.0.2 is assigned to the multicast
routers group.
IGMP (Internet Group Management Protocol) is the protocol used to support
multicast groups. The latest version is version 2 (see RFC2236). IP hosts
use IGMP to report their multicast group membership to any immediate-neighbor
multicast routers so the multicast routers can decide if a multicast packet
needs to be forwarded. At start up, the Prestige queries all directly connected
networks to gather group membership.
After that, the Prestige updates the information by periodic queries.
The Prestige implementation of IGMP is also compatible with version 1.
The multicast setting can be turned on or off on Ethernet and remote nodes.
Enable IGMP in Prestige's LAN in menu 3.2:
Menu 3.2 - TCP/IP and DHCP Setup
DHCP Setup
DHCP= Server
Client IP Pool Starting Address=
192.168.1.33
Size of Client IP Pool=
32
Primary DNS Server=
0.0.0.0
Secondary DNS Server=
0.0.0.0
Remote DHCP Server= N/A
TCP/IP Setup:
IP Address= 192.168.1.1
IP Subnet Mask=
255.255.255.0
RIP Direction=
Both
Version= RIP-1
Multicast=
IGMP-v2
IP Policies=
Edit IP Alias=
No
Press ENTER to Confirm or ESC to Cancel:
|
Enable IGMP in Prestige's remote node in menu 11.3:
Menu 11.3 - Remote Node Network Layer Options IP
Options:
Bridge Options:
Rem IP
Addr:
Ethernet Addr Timeout(min)= N/A
Rem Subnet Mask=
0.0.0.0
My WAN Addr=
0.0.0.0
NAT =
None
Address Mapping Set= N/A
Metric=
2
Private= No
RIP Direction=
Both
Version=
RIP-2B
Multicast= IGMP-v2
IP Policies=
Enter here to CONFIRM or ESC to CANCEL: |
Key Settings:
Multicast |
IGMP-v1 for IGMP version 1, IGMP-v2 for IGMP version 2. |
All contents copyright © 2005 ZyXEL Communications Corporation.