Multicast; Internet Connection; Ethernet Encapsulation - ZyXEL Communications NBG4615 User Manual

17.3.2 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.
Figure 96 Multicast Example
In the multicast example above, systems A and D comprise one multicast group. In multicasting,
the server only needs to send one data stream and this is delivered to systems A and D.
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. The NBG4615 supports both IGMP version 1
(IGMP-v1) and IGMP version 2 (IGMP-v2).
At start up, the NBG4615 queries all directly connected networks to gather group membership.
After that, the NBG4615 periodically updates this information. IP multicasting can be enabled/
disabled on the NBG4615 LAN and/or WAN interfaces in the Web Configurator (LAN; WAN). Select
None to disable IP multicasting on these interfaces.

17.4 Internet Connection

Use this screen to change your NBG4615's Internet access settings. Click WAN from the
Configuration menu. The screen differs according to the encapsulation you choose.

17.4.1 Ethernet Encapsulation

This screen displays when you select Ethernet encapsulation.
NBG4615 User's Guide
Chapter 17 WAN
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