Chapter 6 WAN
LTE5366 Series User’s Guide
56
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 31
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 LTE5366 supports both IGMP version 1 (
IGMP v1
),
IGMP version 2 (
IGMP v2
) and IGMP version 3 (
IGMP v3
).
At start up, the LTE5366 queries all directly connected networks to gather group membership. After that,
the LTE5366 periodically updates this information. IP multicasting can be enabled/disabled on the
LTE5366 WAN interface in the Web Configurator.
IPv6 Introduction
IPv6 (Internet Protocol version 6), is designed to enhance IP address size and features. The increase in
IPv6 address size to 128 bits (from the 32-bit IPv4 address) allows up to 3.4 x 10
38
IP addresses. The LTE5366
can use IPv4/IPv6 dual stack to connect to IPv4 and IPv6 networks, and supports IPv6 rapid deployment
(6RD).
IPv6 Addressing
The 128-bit IPv6 address is written as eight 16-bit hexadecimal blocks separated by colons (:). This is an
example IPv6 address
2001:0db8:1a2b:0015:0000:0000:1a2f:0000
.
IPv6 addresses can be abbreviated in two ways:
• Leading zeros in a block can be omitted. So
2001:0db8:1a2b:0015:0000:0000:1a2f:0000
can be
written as
2001:db8:1a2b:15:0:0:1a2f:0
.
• Any number of consecutive blocks of zeros can be replaced by a double colon. A double colon can
only appear once in an IPv6 address. So
2001:0db8:0000:0000:1a2f:0000:0000:0015
can be
written as
2001:0db8::1a2f:0000:0000:0015
,
2001:0db8:0000:0000:1a2f::0015
,
2001:db8::1a2f:0:0:15
or
2001:db8:0:0:1a2f::15
.
