Security 13-9

Other filter attributes

There are three other attributes to each filter:

■The filter’s order (i.e., priority) in the filter set

■Whether the filter is currently active

■Whether the filter is set to forward packets or to block (discard) packets

Putting the parts together

When you display a filter set, its filters are displayed as rows in a table:

+-#---

Source IP Addr---

Dest IP Addr-----

Proto-Src.Port-D.Port--

On?-Fwd-+

+----------------------------------------------------------------------

 

 

 

 

 

+

1

192.211.211.17

0.0.0.0

TCP

0

23

Yes No

2

0.0.0.0

0.0.0.0

TCP

NC

=6000

Yes No

3

0.0.0.0

0.0.0.0

ICMP

--

--

Yes Yes

4

0.0.0.0

0.0.0.0

TCP

NC

>1023

Yes Yes

5

0.0.0.0

0.0.0.0

UDP

NC

>1023

Yes Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

+----------------------------------------------------------------------

 

 

 

 

 

+

The table’s columns correspond to each filter’s attributes:

#: The filter’s priority in the set. Filter number 1, with the highest priority, is first in the table.

Source IP Addr: The packet source IP address to match.

Dest IP Addr: The packet destination IP address to match.

Proto: The protocol to match. This can be entered as a number (see the table below) or as TCP or UDP if those protocols are used.

Protocol

Number to use

Full name

 

 

 

 

 

 

N/A

0

Ignores protocol type

 

 

 

ICMP

1

Internet Control Message Protocol

 

 

 

TCP

6

Transmission Control Protocol

 

 

 

UDP

17

User Datagram Protocol

 

 

 

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Netopia R5000 manual Other filter attributes, Putting the parts together, Internet Control Message Protocol