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

jerry's blog

熟悉的地方但似乎又很陌生的生活方式.
年代還是不一樣了.

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)。

旧的不去,新的不来

在S公司做了20年(準確的說是7808天,21.39年),因收購又進入了P集團做了4年(1529天,4.19年)。 就在春節過年前,公司小老闆跟我說出了終止與我的合約的事情。 有預感,但依然覺得突然與無奈。 說實在話,受到P公司的作風與文化的衝擊,後來的工作就變得非常「不爽」。一...