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Set — enables the tcp flag, Unset — disables the tcp flag, Don’t care — does not check the packet’s tcp flag – 3Com 2924-PWR User Manual

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78

C

HAPTER

4: M

ANAGING

D

EVICE

S

ECURITY

Select from List — Selects a protocol from a list by which packets
are matched to the rule.

Protocol ID — Adds user-defined protocols by which packets are
matched to the rule. Each protocol has a specific protocol number
which is unique. The possible field range is 0-255.

Source Port — Enables creating an ACL based on a specific protocol.

Any — Enables creating an ACL based on any protocol.

Destination Port — Defines the destination port that is matched to
packets. Enabled only when TCP or UDP are selected in the Protocol
list.

Any — Enables creating an ACL Based on any protocol.

TCP Flags — If checked, enables configuration of TCP flags matched
to the packet. The possible fields are:

Urg — Urgent pointer field significant. The urgent pointer points to
the sequence number of the octet following the urgent data.

Ack — Acknowledgement field significant. The acknowledgement
field is the byte number of the next byte that the sender expects to
receive from the receiver.

Psh — Push (send) the data as soon as possible, without buffering.
This is used for interactive traffic.

Rst — Reset the connection. This invalidates the sequence numbers
and aborts the session between the sender and receiver.

Syn — Synchronize Initial Sequence Numbers (ISNs). This is used to
initialize a new connection.

Fin — Finish. This indicates there is no more data from the sender.
This marks a normal closing of the session between the sender and
receiver.

For each TCP flag, the possible field values are:

Set — Enables the TCP flag.

Unset — Disables the TCP flag.

Don’t Care — Does not check the packet’s TCP flag.