星期四, 10月 12, 2006

What's port 445 used for in Windows 2000/XP?

Among the new ports used by Windows 2000, Windows XP and Windows Server 2003, is TCP port 445 which is used for SMB over TCP.
The SMB (Server Message Block) protocol is used among other things for file sharing in Windows NT/2000/XP. In Windows NT it ran on top of NetBT (NetBIOS over TCP/IP), which used the famous ports 137, 138 (UDP) and 139 (TCP). In Windows 2000/XP/2003, Microsoft added the possibility to run SMB directly over TCP/IP, without the extra layer of NetBT. For this they use TCP port 445.
At its simplest NetBIOS on your LAN may just be a necessary evil. NetBIOS on your WAN or over the Internet, however, is an enormous security risk. All sorts of information, such as your domain, workgroup and system names, as well as account information is obtainable via NetBIOS. It really is in your best interests to ensure that NetBIOS never leaves your network.
If you are using a router as your Internet gateway then you will want to ensure that it does not allow inbound or outbound traffic via TCP ports 135-139.
If you're using a Firewall then you should also block the same ports - TCP ports 135-139.
If you are using a multi-homed machine i.e. more than 1 network card, then you should disable NetBIOS on every network card, or Dial-Up Connection under the TCP/IP properties, that is not part of your local network.

星期一, 10月 09, 2006

星期日, 10月 08, 2006

电子图书

电子图书

提供的10000本书均为PDF格式,阅读前请先下载安装阅读器,如系统已安装相应阅读器可跳过此项(英文Adobe Acrobat可能会要求安装亚洲语言支持)。

「行山」摸摸獅子頭

秋高氣爽的日子。 上週與公司同事走了港島的龍脊,風光很美。但因為領隊(不是我)走得太急,引致同行的女同事埋怨難度太高,怪到我的提議者來了。哈哈。 這次帶大婆這個「蟻行者」出動,目標是上個禮拜的候補路線:獅子山。帶老婆行上倒是比較輕鬆,只要我能走的她也基本上ok。因為她會按自己的能...