您想知道在您的网络中的每台计算机或设备上找到多少个开放端口吗？(computer or device)你想评估他们的防火墙保护有多好以及他们有多脆弱吗？然后，您应该尝试Nmap - 一个用于安全审计的(security auditing)开源工具(source tool)。我们在对安全解决方案的评论中使用它，我们认为它很棒。你也应该尝试一下。
介绍Nmap 和 Zenmap(Nmap & Zenmap) -安全扫描器(Security Scanner)
Nmap的意思是“网络映射器(Network Mapper)”，它是一个用于网络发现和安全审计的(network discovery and security auditing)命令行工具(command line tool)。它是免费的、开源的和多平台(source and multiplatform)的。它可以在Windows、Linux 和 Mac OS X(Linux and Mac OS X)上运行。它能够处理一些非常先进的东西，这就是为什么它被世界各地的许多网络管理员和安全专业人员使用。
我提到它是一个命令行工具(command line tool)。这肯定会关闭不喜欢命令提示符(Command Prompt)的人。幸运的是，还有Zenmap——一个为(Zenmap)Nmap提供可视化界面的特殊客户端。
您可以从这里下载它：Nmap for Windows。寻找写着“Latest release self-installer”的行。那就是带有Windows可视化界面的(Windows)Nmap 客户端(Nmap client)。显然，它可以在Windows 7和Windows 8上运行。
将其安装在您要进行审核的计算机上，而不是您要评估的计算机上。
如何扫描网络(Your Network)上的计算机和设备(Computers & Devices)
使用开始菜单(Start Menu)（在 Windows 7 中）或开始(Start)屏幕（在 Windows 8 中）中的快捷方式启动Zenmap 。
打开您要评估的计算机和设备，并确保它们已连接到网络。然后，在Zenmap窗口中，查找目标(Target)字段。键入要扫描的计算机或设备的(computer or devices)IP 地址。(IP address)您也可以使用计算机名称(computer name)，如果您知道它更方便。
在配置文件(Profile)字段中，选择您要执行的扫描类型。通常(Generally)，密集扫描提供了一个很好的概览，并且结束相对较快。
接下来，按下扫描(Scan)按钮，将显示UAC 提示(UAC prompt)。确认您要继续扫描并等待。在Nmap 输出(Nmap Output)选项卡中，您会看到很多活动正在进行。扫描结束后，该选项卡中的最后一行会显示“Nmap done”。
现在您可以阅读Nmap 输出(Nmap Output)选项卡中显示的所有信息并检查其他可用选项卡。
Ports/Hosts选项卡列出了所有打开的端口。
拓扑(Topology)选项卡共享您扫描的计算机/设备在网络中相对于您进行扫描的计算机的位置的可视化概览。
Host Details选项卡共享Nmap发现的可视化概览。这将很快成为您最喜欢的标签，因为它以非常易于理解的格式共享所有内容。
扫描(Scans)选项卡仅共享您使用Zenmap进行的扫描的历史记录。
在右侧，在默认启用的Hosts按钮附近，您有(Hosts)Services按钮。单击(Click)它，Zenmap将根据每个网络服务(per network service basis)过滤其选项卡中显示的所有信息。
您可以使用您执行的扫描结果来加强网络计算机和设备上的防火墙保护。(firewall protection)然后，您可以执行其他扫描并使用Zenmap来比较结果。
Zenmap存储完整的扫描历史记录，并且使用“(Zenmap)工具(Tools)”菜单可以轻松进行比较。
结论
如前所述，Nmap及其可视化用户界面客户端(user interface client)Zenmap 是非常复杂的工具。在本指南中，我只触及了他们可以做的事情的皮毛。因此，不要犹豫，尝试一下，实验并阅读官方文档：Nmap 参考指南(Nmap Reference Guide)。你会发现很多好东西可以阅读和学习。
Scan for Open Ports & Evaluate the Security of Your System with Nmap
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Introducing Nmap & Zenmap - the Security Scanner
Nmap means "Network Mapper" and it is a command line tool for network discovery and security auditing. It is free, open source and multiplatform. It can run on Windows, Linux and Mac OS X. It is capable of some really advanced stuff and that's why it is used by many network administrators and security professionals all over the world.
I mentioned that it is a command line tool. This will definitely turn off people who do not love the Command Prompt. Luckily, there is also Zenmap - a special client which provides a visual interface for Nmap.
You can download it from here: Nmap for Windows. Look for line that says "Latest release self-installer". That's the Nmap client with a visual interface for Windows. Obviously, it runs on both Windows 7 and Windows 8.
Install it on the computer from where you want to do the auditing, not on the one you want evaluated.
How to Scan the Computers & Devices on Your Network
Launch Zenmap using its shortcut on in the Start Menu (in Windows 7) or the Start screen (in Windows 8).
Turn on the computers and devices you want to evaluate and make sure they are connected to the network. Then, in the Zenmap window, look for the Target field. Type the IP address of the computer or devices you want to scan. You can also use the computer name, if you know it and it is more convenient.
The, in the Profile field, select the type of scan you want to perform. Generally, the intense scan provides a good overview and it is over relatively fast.
Next, press the Scan button and a UAC prompt is shown. Confirm that you want to go ahead with the scan and wait. In the Nmap Output tab, you will see lots of activity going on. When the scan is over, the last line in that tab will say "Nmap done".
Now you can read all the information displayed in the Nmap Output tab and check the other tabs available.
The Ports/Hosts tab lists all the ports that were found open.
The Topology tab shares a visual overview of how the computer/device you have scanned is positioned in the network, relative to the computer from where you made the scan.
The Host Details tab shares a visual overview of the Nmap's findings. This will quickly become your favorite tab as it shares everything in a very digestible format.
The Scans tab only shares the history of the scans you have made with Zenmap.
On the right, near the Hosts button, which is enabled by default, you have the Services button. Click on it, and Zenmap will filter all the information displayed in its tabs, on a per network service basis.
You can use the results of the scans you perform to harden the firewall protection on your network computers and devices. Then, you can perform other scans and use Zenmap to compare the results.
Zenmap stores a complete history of your scans and comparisons are easy to make, using the Tools menu.
Conclusion
As mentioned before Nmap and its visual user interface client - Zenmap, are very complex tools. In this guide I've only scratched the surface of what they can do. Therefore, don't hesitate to try them out, experiment and also read the official documentation: Nmap Reference Guide. You will find plenty of good stuff to read and learn.
