Configuring IP Filters

 

 

Store State:

When this option is enabled, packets are monitored for their state

 

(i.e., whether they are the initiating packet or a subsequent packet

 

in an ongoing communication, etc). This option provides

 

a degree of security by blocking/dropping packets that are not

 

received in the anticipated state. Such packets can signify

 

unwelcome attempt to gain access to a network.

 

 

Source Port:

These are the port number criteria for the source computer(s)

Dest Port:

(from which the packet originates) and destination computers.

 

 

Port numbers identify the type of traffic that the computer or

 

server can handle and are specified by the Internet Assigned

 

Numbers Authority (IANA). For example, port number 80

 

indicates a Web server, 21 indicates an FTP server.

 

You can choose a port type by name from the drop-down lists or,

 

if not available in the list, specify the IANA port number in the text

 

boxes. Select any other port if the criteria will not be used.

 

These fields will be dimmed (unavailable for entry) unless you

 

have selected [TCP] or [UDP] as the protocol.

 

See the description of [Src IP Address] for the statement options

 

([any], [eq], [gt], etc.)

 

 

TCP Flag:

This field specifies whether the rule should apply only to TCP

 

packets that contain the synchronous (SYN) flag, only to those

 

that contain the non-synchronous (NOT-SYN) flag, or to all TCP

 

packets. This field will be dimmed (unavailable for entry) unless you

 

selected [TCP] as the protocol.

 

 

ICMP Type:

This field specifies whether the value in the type field in ICMP

 

packet headers will be used as criteria. The code value can be

 

any decimal value from [0-255]. You can specify that the value

 

must equal ([eq]) or not equal ([neq]) the specified value,

 

or you can select [any] to enable the rule to be invoked on

 

all ICMP packets. This field will be dimmed (unavailable for entry)

 

unless you specify [ICMP] as the protocol.

 

 

ICMP Code:

This field specifies whether the value in the code field in ICMP

 

packet headers will be used as criteria. The code value can be

 

any decimal value from [0-255]. You can specify that the value

 

must equal ([eq]) or not equal ([neq]) the specified value,

 

or you can select [any] to enable the rule to be invoked on

 

all ICMP packets. This field will be dimmed (unavailable for entry)

 

unless you specify ICMP as the protocol.

 

 

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SMC Networks SMC7204BRA manual Store State, An ongoing communication, etc. This option provides, Any, eq, gt, etc