Port Number Comparisons; Other Filter Attributes - Motorola 2200 Administrator's Handbook

Administrator's Handbook
By matching on a port number, a filter can be applied to selected TCP or UDP services, such as Telnet, FTP,
and World Wide Web. The following tables show a few common services and their associated port numbers:
Internet service
FTP
Telnet
SMTP (mail)
Gopher
Internet service
Who Is
World Wide Web
SNMP

Port number comparisons

A filter can also use a comparison option to evaluate a packet's source or destination port number. The
comparison options are:
• No Compare: No comparison of the port number specified in the filter with the packet's port number.
•
Not Equal To: For the filter to match, the packet's port number cannot equal the port number specified
in the filter.
• Less Than: For the filter to match, the packet's port number must be less than the port number speci-
fied in the filter.
•
Less Than or Equal: For the filter to match, the packet's port number must be less than or equal to the
port number specified in the filter.
•
Equal: For the filter to match, the packet's port number must equal the port number specified in the fil-
ter.
•
Greater Than: For the filter to match, the packet's port number must be greater than the port number
specified in the filter.
•
Greater Than or Equal: For the filter to match, the packet's port number must be greater than or equal
to the port number specified in the filter.
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
166
TCP port Internet service
20/21 Finger
23 World Wide Web
25 News
70 rlogin
UDP port Internet service
43 TFTP
80 who
161
TCP port
79
80
144
513
UDP port
69
513