Security 13-7

Internet service

TCP port

Internet service

TCP port

 

 

 

 

 

 

 

 

FTP

20/21

Finger

79

 

 

 

 

Telnet

23

World Wide Web

80

 

 

 

 

SMTP (mail)

25

News

144

 

 

 

 

Gopher

70

rlogin

513

 

 

 

 

 

 

 

 

Internet service

UDP port

Internet service

UDP port

 

 

 

 

 

 

 

 

Who Is

43

AppleTalk Routing

202

 

 

Maintenance (at-rtmp)

 

 

 

 

 

World Wide Web

80

AppleTalk Name Binding

202

 

 

(at-nbp)

 

 

 

 

 

SNMP

161

AURP (AppleTalk)

387

 

 

 

 

TFTP

69

who

513

 

 

 

 

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 specified 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 filter.

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.

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Netopia 4753 manual Internet service TCP port, Aurp AppleTalk 387, Who 513, Port number comparisons