ZyXEL g-2000 plusv2 Guia Do Utilizador

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ZyXEL G-2000 Plus v2 User’s Guide
Chapter 28 Filter Configuration
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28
Filter Configuration
This chapter shows you how to create and apply filters.
28.1  Introduction to Filters
Your ZyXEL device uses filters to decide whether to allow passage of a data packet and/or to 
make a call. There are two types of filter applications: data filtering and call filtering. Filters 
are subdivided into device and protocol filters, which are discussed later.
Data filtering screens the data to determine if the packet should be allowed to pass. Data filters 
are divided into incoming and outgoing filters, depending on the direction of the packet 
relative to a port. Data filtering can be applied on either the WAN side or the LAN side. Call 
filtering is used to determine if a packet should be allowed to trigger a call. Remote node call 
filtering is only applicable when using PPPoE encapsulation. Outgoing packets must undergo 
data filtering before they encounter call filtering as shown in the following figure.
Figure 159   Outgoing Packet Filtering Process
For incoming packets, your ZyXEL device applies data filters only. Packets are processed 
depending upon whether a match is found. The following sections describe how to configure 
filter sets.