ZyXEL Communications USG 2000 User Manual

Chapter 32 Application Patrol

ZyWALL USG 2000 User’s Guide

• The outbound traffic flows from the connection initiator to the connection 

responder. 

• The inbound traffic flows from the connection responder to the connection 

initiator. 

For example, a LAN to WAN connection is initiated from LAN and goes to the WAN.

• Outbound traffic goes from a LAN zone device to a WAN zone device. Bandwidth 

management is applied before sending the packets out a WAN zone interface on 

the ZyWALL. 

• Inbound traffic comes back from the WAN zone device to the LAN zone device. 

Bandwidth management is applied before sending the traffic out a LAN zone 

interface. 

LAN

 to WAN Connection and Packet Directions     

You can limit an application’s outbound or inbound bandwidth. This limit keeps the 
traffic from using up too much of the out-going interface’s bandwidth. This way 
you can make sure there is bandwidth for other applications. When you apply a 
bandwidth limit to outbound or inbound traffic, each member of the out-going 
zone can send up to the limit. Take a LAN to WAN policy for example. 

• Outbound traffic is limited to 200 kbps. The connection initiator is on the LAN so 

outbound means the traffic traveling from the LAN to the WAN. Each of the WAN 

zone’s two interfaces can send the limit of 200 kbps of traffic.  

• Inbound traffic is limited to 500 kbs. The connection initiator is on the LAN so 

inbound means the traffic traveling from the WAN to the LAN. 

Figure 383   LAN to WAN, Outbound 200 kbps, Inbound 500 kbps  

 

 

Inbound

Outbound

Outbound

500 kbps

200 kbps

200 kbps