Chapter 7 Interfaces

•An interface is a logical entity through which (layer-3) packets pass.

•An interface is bound to a physical port or another interface.

•Many interfaces can share the same physical port.

•An interface belongs to at most one zone.

•Many interfaces can belong to the same zone.

•Layer-3 virtualization (IP alias, for example) is a kind of interface.

Types of Interfaces

You can create several types of interfaces in the ZyWALL.

•Setting interfaces to the same port role forms a port group. Port groups create a hardware connection between physical ports at the layer-2 (data link, MAC address) level. Port groups are created when you use the Interface > Port Roles screen to set multiple physical ports to be part of the same interface.

•Ethernet interfaces are the foundation for defining other interfaces and network policies. RIP and OSPF are also configured in these interfaces.

•Tunnel interfaces send IPv4 or IPv6 packets from one network to a specific network through the Internet or a public network.

•VLAN interfaces receive and send tagged frames. The ZyWALL automatically adds or removes the tags as needed. Each VLAN can only be associated with one Ethernet interface.

•Bridge interfaces create a software connection between Ethernet or VLAN interfaces at the layer-2 (data link, MAC address) level. Unlike port groups, bridge interfaces can take advantage of some security features in the ZyWALL. You can also assign an IP address and subnet mask to the bridge.

•PPP interfaces support Point-to-Point Protocols (PPP). ISP accounts are required for PPPoE/PPTP interfaces.

•Cellular interfaces are for 3G WAN connections via a connected 3G device.

•Virtual interfaces provide additional routing information in the ZyWALL. There are three types: virtual Ethernet interfaces, virtual VLAN interfaces, and virtual bridge interfaces.

•Trunk interfaces manage load balancing between interfaces.

Port groups and trunks have a lot of characteristics that are specific to each type of interface. The other types of interfaces--Ethernet, PPP, cellular, VLAN, bridge, and virtual--have a lot of similar characteristics. These characteristics are listed in the following table and discussed in more detail below.

Table 37 Ethernet, PPP, Cellular, VLAN, Bridge, and Virtual Interface Characteristics

CHARACTERISTICSETHERNET

ETHERNET

PPP

CELLULARVLANBRIDGEVIRTUAL

Name*

wan1

lan1, lan2,

pppx

cellularx

vlanx

brx

**

 

 

dmz

 

 

 

 

 

 

 

 

 

 

 

 

 

Configurable Zone

No

No

Yes

Yes

Yes

Yes

No

IP Address Assignment

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Static IP address

Yes

Yes

Yes

Yes

Yes

Yes

Yes

DHCP client

Yes

No

Yes

Yes

Yes

Yes

No

Routing metric

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Interface Parameters

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bandwidth

Yes

Yes

Yes

Yes

Yes

Yes

Yes

restrictions

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

104

 

ZyWALL 110/310/1100 Series User’s Guide