Multicast; The Broadband Screen; Ethernet Encapsulation - ZyXEL Communications NBG5715 User Manual

10.3.2 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 38 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 NBG5715 supports both IGMP version 1
(IGMP-v1) and IGMP version 2 (IGMP-v2).
At start up, the NBG5715 queries all directly connected networks to gather group membership.
After that, the NBG5715 periodically updates this information. IP multicasting can be enabled/
disabled on the NBG5715 LAN and/or WAN interfaces in the Web Configurator (LAN; WAN). Select
None to disable IP multicasting on these interfaces.

10.4 The Broadband Screen

Use this screen to change your NBG5715's Internet access settings. Click Configuration >
Network > WAN to open the Broadband screen. The screen differs according to the
encapsulation you choose.

10.4.1 Ethernet Encapsulation

This screen displays when you select ENET ENCAP (Ethernet encapsulation).
NBG5715 User's Guide
Chapter 10 WAN
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