ADSL Router User Manual
The information added will be shown on the window right away, as the right figure illustrates. That is, the specified address will be reserved and not be assigned by DHCP for other computer(s).
You may click Add button to add another set or click Close to exit.
Local Network – UPnP
The UPnP is only available for Windows XP. If you are not a Windows XP user, you may ignore this page.
Enabling the UPnP IGD and NAT traversal function allows the users to perform more applications behind NAT without additional configuration settings or ALG support on your ADSL Router.
You can enable the UPnP function through this web page by checking Enable UPnP and press Apply.
Local Network – IGMP Snooping
Traditionally, IP packets are transmitted in one of either two ways - Unicast (1 sender to 1 recipient) or Broadcast (1 sender to everyone on the network). Multicast delivers IP packets to just a group of hosts on the network.
Without IGMP snooping, multicast traffic is treated in the same manner as broadcast traffic, that is, it is forwarded to all ports. With IGMP snooping, multicast traffic of a group is only forwarded to ports that have members of that group. IGMP snooping generates no additional network traffic, allowing you to significantly reduce multicast traffic passing through your switch.
The figure below shows a simple network connected via this ADSL router. There are four Ethernet clients, one using USB, and two wireless clients.
Now suppose the video server is the multicast transmitter and host A and D are multicast receivers. If we do not turn on the IGMP snooping function, the router will
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