P314 Broadband Sharing Gateway with 4-Port Switch

Packet

into IP Filter

Filter Active?

N o

Yes

Apply SrcAddrMask

to Src Addr

Check Src

IP Addr

Not Matched

Matched

Apply DestAddrMask

to Dest Addr

Check Dest

IP Addr

Not Matched

Matched

Check

Not Matched

IP Protocol

Matched

 

 

 

Check Src &

Not Matched

 

 

Dest Port

 

 

 

 

 

Matched

 

 

 

More?

Yes

 

 

N o

 

Action Not Matched

Action Matched

Check Next Rule

 

 

 

Check Next Rule

Drop

Forward

Drop

Forward

 

 

Drop Packet

Check Next Rule

 

Accept Packet

Figure 7-8 Executing an IP Filter

7-10

Filter Configuration