Ericsson EFN324, User Manual, Page: 39 / 176

Glossary
Figure 18 Switching Domain with Uplink and Transit Link
5.3.2 Switching Domain Switching Rule Modes
Each switching domain works according to one of the following switching rule
modes:

Normal

Uplink

GW

IP validation

GW + IP validation

IP vali virtual MAC

GW + IP vali virtual MAC

PPPoE
The
normal
mode means that packets are switched according to the content
in the bridge table. The bridge table content is maintained according to the
self­learning bridge principle. When a destination address is not found in the
table, the packet is forwarded (flooded) to all other ports in the switching
domain.
The effects of defining an
uplink
were described previously. When an uplink is
defined, a gateway can also be defined. This is discussed further in section 8.1
on page 60.
When a gateway is defined, all packets not originating from the uplink will
have their destination MAC addresses rewritten as the MAC address of the
gateway, before they are sent on the uplink. This mechanism is known as MAC
forced forwarding. Packets arriving from the uplink must have the gateway as
their source address in the Layer 2 network.
Please note that:

if the gateway is left undefined then DHCP and ARPs will be resolved for
multiple end user in same port

if the gateway is configured then DHCP and ARPs will be resolved for
multiple end user tags in same port only if multiple switching domains are
used, i.e. unique switching domain should configure for that user tag; in
other words, it is possible to have DHCP only for one user tag specific per
port and per switching domain
o
in case each user needs several services it is necessary to
configure a Switching Domain per service