3Com 2924-SFP User Manual page 72

72 C 4: M
HAPTER ANAGING
D S
EVICE ECURITY
For each TCP flag, the possible field values are:
Set — Enables the TCP flag.
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Unset — Disables the TCP flag.
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Don't Care — Does not check the packet's TCP flag.
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ICMP — If checked, enables filtering ICMP packets for an ICMP
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message type. The possible values are:
Select from List — Selects an ICMP message type from a list.
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ICMP Type — Specifies an ICMP message type.
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Any — Does not filter for an ICMP message type.
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ICMP Code — If checked, enables specifying an ICMP message code
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for filtering ICMP packets. ICMP packets that are filtered by ICMP
message type can also be filtered by the ICMP message code.
IGMP — If checked, enables filtering IGMP packets for an IGMP
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message type. The possible values are:
Select from List — Selects an IGMP message type from a list.
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IGMP Type — Specifies an IGMP message type.
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Any — Does not filter for an IGMP message type.
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Source IP Address — Matches the source IP address to which
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packets are addressed to the ACL.
Wild Card Mask — Defines the source IP address wildcard mask.
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Wildcard masks specify which bits are used and which bits are
ignored. A mask of 255.255.255.255 indicates that no bit is
important. A mask of 0.0.0.0 indicates that all the bits are
important. For example, if the source IP address is 149.36.184.198
and the wildcard mask is 255.255.255.00, the first three bytes of
the IP address are ignored, while the last eight bits are used.
Destination IP Address — Matches the destination IP address to
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which packets are addressed to the ACL.
Wild Card Mask — Indicates the destination IP Address wildcard
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mask. Wildcards are used to filter a destination IP Address. Masks
specify which bits are used and which bits are ignored. A wildcard
mask of 255.255.255.255 indicates that no bit is important. A
wildcard mask of 0.0.0.0 indicates that all bits are important. For
example, if the destination IP address 149.36.184.198 and the
wildcard mask is 255.255.0.0, the first two bytes of the IP address
are used, while the last two bytes are ignored.