3Com 3CBLSG48 User Manual page 79

8 C 4: M
HAPTER ANAGING
D S
EVICE ECURITY
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.
Source IP Address — If selected, enables matching the source
port IP address to which packets are addressed to the ACE,
according to a wildcard mask. The field value is either user defined
or Any. If Any is selected, accepts any source IP address and disables
wildcard mask filtering.
Wild Card Mask — Defines the source IP address wildcard
mask. Wildcard 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 the bits are
important. For example, if the source IP address is
149.36.184.198 and the wildcard mask is 0.0.0.255, the first
three bytes of the IP address are matched, while the last
eight bits are ignored. For the source IP address
149.36.184.198, this wildcard mask matches all IP addresses
in the range 149.36.184.0 to 149.36.184.255. A wildcard
mask must not contain leading zeroes. For example, a
wildcard mask of 010.010.011.010 is invalid, but a wildcard
mask of 10.10.11.10 is valid.