ZyXEL Communications ZYWALL USG 20 - Page 275

Chapter 11 Interfaces
ZyWALL USG 20/20W User’s Guide
275
If computer B responds to computer A, bridge X records the source address
0B:0B:0B:0B:0B:0B and port 4 in the table. It also looks up 0A:0A:0A:0A:0A:0A
in the table and sends the packet to port 2 accordingly.
Bridge Interface Overview
A bridge interface creates a software bridge between the members of the bridge
interface. It also becomes the ZyWALL’s interface for the resulting network.
Unlike the device-wide bridge mode in ZyNOS-based ZyWALLs, this ZyWALL can
bridge traffic between some interfaces while it routes traffic for other interfaces.
The bridge interfaces also support more functions, like interface bandwidth
parameters, DHCP settings, and connectivity check. To use the whole ZyWALL as a
transparent bridge, add all of the ZyWALL’s interfaces to a bridge interface.
A bridge interface may consist of the following members:
• Zero or one WLAN interfaces
• Zero or one VLAN interfaces (and any associated virtual VLAN interfaces)
• Any number of Ethernet interfaces (and any associated virtual Ethernet
interfaces)
When you create a bridge interface, the ZyWALL removes the members’ entries
from the routing table and adds the bridge interface’s entries to the routing table.
For example, this table shows the routing table before and after you create bridge
interface br0 (250.250.250.0/23) between lan1 and vlan1.
In this example, virtual Ethernet interface lan1:1 is also removed from the routing
table when lan1 is added to br0. Virtual interfaces are automatically added to or
Table 68 Example: Bridge Table After Computer B Responds to Computer A
MAC ADDRESS PORT
0A:0A:0A:0A:0A:0A 2
0B:0B:0B:0B:0B:0B 4
Table 69 Example: Routing Table Before and After Bridge Interface br0 Is Created
IP ADDRESS(ES) DESTINATION IP ADDRESS(ES) DESTINATION
210.210.210.0/24 lan1 221.221.221.0/24 vlan0
210.211.1.0/24 lan1:1 230.230.230.192/26 wan
221.221.221.0/24 vlan0 241.241.241.241/32 dmz
222.222.222.0/24 vlan1 242.242.242.242/32 dmz
230.230.230.192/26 wan 250.250.250.0/23 br0
241.241.241.241/32 dmz
242.242.242.242/32 dmz