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 R5200, R5300, R5100 manual Other filter attributes, Putting the parts together, Internet Control Message Protocol