ZyXEL Communications 202H User Manual

Prestige 202H User’s Guide 

Filter Configuration 

 

18-1 

 

Your Prestige uses filters to decide whether or not 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 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 Ethernet side. Call filtering is used to determine if a packet should 
be allowed to trigger a call. 

Outgoing packets must undergo data filtering before they encounter call filtering. Call filters are divided 
into two groups, the built-in call filters and user-defined call filters. Your Prestige has built-in call filters 
that prevent administrative, for example, RIP packets from triggering calls. These filters are always enabled 
and not accessible to you. Your Prestige applies the built-in filters first and then the user-defined call filters, 
if applicable, as shown next.