Security
Denial of Service Prevention
Cisco 350XG & 550XG Series 10G Stackable Managed Switches
437
19
-
0.0.0.0/8 (Except 0.0.0.0/32 as a Source Address)
—Addresses in
this block refer to source hosts on this network.
-
127.0.0.0/8
—Used as the Internet host loopback address.
-
192.0.2.0/24
—Used as the TEST-NET in documentation and example
codes.
-
224.0.0.0/4 (As a Source IP Address)
—Used in IPv4 Multicast address
assignments, and was formerly known as Class D Address Space.
-
240.0.0.0/4 (Except 255.255.255.255/32 as a Destination
Address)
—Reserved address range, and was formerly known as Class
E Address Space.
You can also add new Martian Addresses for DoS prevention. Packets that have a
Martian addresses are discarded.
To define Martian addresses:
STEP 1
Click
Security
>
Denial of Service Prevention
>
Martian Addresses
.
STEP 2
Select
Reserved Martian Addresses
and click
Apply
to include the reserved
Martian Addresses in the System Level Prevention list.
STEP 3
To add a Martian address click
Add
.
STEP 4
Enter the parameters.
•
IP Version
—Indicates the supported IP version. Currently, support is only
offered for IPv4.
•
IP Address
—Enter an IP addresses to reject. The possible values are:
-
From Reserved List
—Select a well-known IP address from the reserved
list.
-
New IP Address
—Enter an IP address.
•
Mask
—Enter the mask of the IP address to define a range of IP addresses to
reject. The values are:
-
Network Mask
—Network mask in dotted decimal format.
-
Prefix Length
—Enter the prefix of the IP address to define the range of IP
addresses for which Denial of Service prevention is enabled.
STEP 5
Click
Apply
. The Martian addresses are written to the Running Configuration file.
