Information Technology Reference
In-Depth Information
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\
Parameters\FirewallPolicy\
<Profile>
\]
"DisableUnicastResponsesToMulticastBroadcast"=dword:1
Using VBScript
This code disables unicast responses to broadcast or multicast traffic.
Set Firewall = CreateObject("HNetCfg.FwMgr")
Set Policy = Firewall.LocalPolicy.CurrentProfile
Policy. UnicastResponsestoMulticastBroadcastDisabled = TRUE
' set this to FALSE to enable broadcast/multicast responses
WScript.Echo "Unicast disabled"
How It Works
When a Windows Server 2003 computer sends a multicast or broadcast packet, it will drop any
unicast packets sent in response to the broadcast that are not received within three seconds. By
enabling the Prohibit Unicast Response to Multicast or Broadcast Requests setting, Windows
Firewall will drop any packet received in response to broadcast or multicast traffic. (The default
setting for this behavior is Not Configured.)
The exception to this setting is that Windows Firewall will permit traffic associated with a
DHCP lease request. However, this setting can interfere with broadcast-based NetBIOS name
resolution, since responses to a NetBIOS broadcast will be dropped, preventing the computer
from resolving a NetBIOS name to an IP address using broadcasts. If your network uses WINS
for NetBIOS name resolution, this problem will be alleviated.
See Also
Microsoft TechNet: “Computer Names Do Not Resolve When Used in a UNC Path”
(
http://technet2.microsoft.com/WindowsServer/en/Library/
b8b1438d-8871-406d-a366-75f1f3a815e91033.mspx
)
3-15. Resetting the Windows Firewall
Problem
You want to reset the Windows Firewall to its default protection settings.
Solution
Using a Graphical User Interface
1.
Open the Network Connections applet.
2.
Double-click on the Local Area Connection icon.
3.
From the Advanced tab, click Settings. This will launch the Windows Firewall Control
Panel applet.
