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SynAttackProtect
Updated: March 28, 2003
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
SynAttackProtect
HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
| Data type | Range | Default value |
|---|---|---|
|
REG_DWORD |
0 | 1 |
0 |
Description
Specifies whether the SYN flooding attack protection feature of TCP/IP is enabled. SYN flooding attack protection is enabled when the value of this entry is 1 and the value of the TcpMaxConnectResponseRetransmissions entry is at least 2 (see note below).
The SYN flooding attack protection feature of TCP detects symptoms of denial-of-service attacks (also known as SYN flooding), and it responds by reducing the time that the server spends on connection requests that it cannot acknowledge.
| Value | Meaning |
|---|---|
|
0 |
SYN flooding attack protection is not enabled. |
|
1 |
SYN flooding attack protection is enabled. |
Notes
-
This value is used only when the number of SYN-ACK retransmissions is likely to impair the server, that is, when the value of the TcpMaxConnectResponseRetransmissions entry is at least 2.
-
Windows Server 2003 does not add this entry to the registry. You can add it by using the registry editor Regedit.exe.
