wi-fi数据双通道

Wi-Fi protocol supports 13 communication channels; how do these channels relate to the volume of devices you can have on the network and the quality of the connection? Read on learn more about Wi-Fi channel usage.

Wi-Fi协议支持13个通信通道； 这些通道与网络上可容纳的设备数量以及连接质量有何关系？ 继续阅读以了解有关Wi-Fi频道使用情况的更多信息。

Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-drive grouping of Q&A web sites.

今天的问答环节由SuperUser提供，它是Stack Exchange的一个分支，它是Q＆A网站的社区推动组织。

问题 (The Question)

SuperUser reader Diogo needs a little clarification on the function of Wi-Fi frequency channels:

SuperUser阅读器Diogo需要对Wi-Fi频道的功能进行一些说明：

As  reference, 802.11 standards (which defines Wi-fi networks) tell us that wireless networks works with 13 different channels on OFDM (depending on the release, a, b, g or n). From this I was wondering, if I have more than 13 machines on the same room (one room work for example with 50 notebooks), it would be impossible to connect all of them to internet at the same time? I mean, each device would use one specific channel to communicate with the acess point, limiting the acess point to 13 permanent connections.

作为参考，802.11标准(定义了Wi-fi网络)告诉我们，无线网络可在OFDM上使用13个不同的通道(取决于版本，a，b，g或n)。 由此我想知道，如果我在同一个房间中有13台以上的机器(例如，一个房间可容纳50个笔记本)，那么是否不可能将所有这些机器同时连接到Internet？ 我的意思是，每个设备将使用一个特定的通道与访问点进行通信，从而将访问点限制为13个永久连接。

How does all this stuff really work?

这些东西如何真正起作用？

Much of modern computing technology is hidden from the end user and Wi-Fi is certainly no exception. How exactly do the Wi-Fi channels relate to network traffic volume and quality?

最终用户隐藏了许多现代计算技术，Wi-Fi当然也不例外。 Wi-Fi通道与网络流量和质量的关系如何？

答案 (The Answer)

Several SuperUser contributors answered Diogo’s question. Joel Coehoorn replies:

几位SuperUser贡献者回答了Diogo的问题。 Joel Coehoorn回复：

First of all, the U.S. only allows 11 of those 13 channels. Additionally, the original wifi developers made a mistake, of sorts, and signals within channels bleed over to their neighbors… there are really only 3 channels you should use: 1, 6 and 11.

首先，美国只允许这13个频道中的11个。 此外，最初的wifi开发人员犯了某种错误，并且通道内的信号渗漏到了邻居… 实际上，您只应使用3个通道：1、6和11 。

That said, you can have far more than 3 devices on wifi at a time, because devices will share time on each channel. It’s just like having someone listen to several conversations taking place at once in a crowded room: not everyone is talking all the time. If two people talk at the same time, the listener may have to ask one or both to repeat themselves. The more people you add to the room, the less total information you can pass around, because people will constantly interrupt one another at an increasing rate. A good rule of thumb is around 25 devices per channel for casual browsing, but this can drop significantly for non-casual traffic like gaming, p2p file sharing, video streaming, and large file transfers.

也就是说，您一次可以在wifi上使用3台以上的设备，因为设备将在每个频道上共享时间。 就像有人在拥挤的房间里一次听几个对话一样：并不是每个人都一直在讲话。 如果两个人同时讲话，则收听者可能不得不请一个或两个重复一次。 您添加到会议室中的人越多，您传递的信息越少，因为人们会不断地互相干扰。 一个好的经验法则是，每个频道大约25个设备可以随意浏览，但是对于非临时性流量(例如游戏，p2p文件共享，视频流和大文件传输)，该数量会大大下降。

In networking parlance, we say a wifi cell is unswitched and half-duplex, making it very sensitive to collisions. Wired networks typcially don’t have these weaknesses (switched and full-duplex), and so while wifi is a “good enough” technology to use at home, serious networks always like to push as many people to a wired connection as possible.

用网络术语来说，我们说wifi单元是未切换的并且是半双工的，因此对冲突非常敏感。 有线网络通常没有这些弱点(交换式和全双工)，因此，尽管wifi是在家中使用的“足够好”的技术，但严肃的网络始终希望将尽可能多的人推向有线连接。

I run the campus network at a small college, and it’s sad to see how many new students arrive this year who have never used a wire for network access. They think the notion of needing a wire is quaint, and don’t understand the physical limitations involved, and why 80 devices (nearly 2 per student on average) in dorm space the size of their parents’ house doesn’t work so well. Re-educating them about this is hard.

我跑在小型大学校园网，这是悲伤地看到许多新的学生如何在今年谁从未用于网络接入线到达。 他们认为需要电线的想法很古怪，不了解所涉及的身体限制，以及为什么宿舍空间中80台设备(平均每位学生将近2台设备)无法达到父母家的大小。 对他们进行重新教育非常困难。

Kurtnelle highlights some frequency channel considerations:

Kurtnelle重点介绍了一些频道注意事项：

Just adding my 2 cents:

只需加上我的2美分：

1. All Access points, and devices are sharing the channel. So if there are 10 access points and 200 devices on channel 6 (regardless of if they are yours or not) are sharing the capacity of the channel. For the G protocol that would be ~50 Mbps, for N ~150Mbps.
   所有接入点和设备正在共享通道。 因此，如果通道6上有10个接入点和200个设备(无论它们是否属于您)，都在共享该通道的容量。 对于G协议，约为50 Mbps，对于N约为150Mbps。
2. Devices and access points (or routers) time share sending and receiving data on the channel. Each device on the channel takes turns sending and receiving data.
   设备和接入点(或路由器)分时在通道上发送和接收数据。 通道上的每个设备轮流发送和接收数据。
3. Some advanced routers can communicate on 2 and 3 channels at once! This requires more compute power of course but it is possible. The really advanced devices are able to filter out devices that are not on its “network” and improve speed performance for it’s devices.
   一些高级路由器可以同时在2个和3个通道上通信！ 当然，这需要更多的计算能力，但是有可能。 真正先进的设备能够过滤掉不在其“网络”上的设备，并提高其设备的速度性能。
4. Wireless N uses the 5Ghz frequency spectrum which is newer, which relates to less devices being on those frequencies.
   无线N使用较新的5Ghz频谱，这与在这些频率上的较少设备有关。

To answer your question in short: You could have thousands of devices on your network; theoretically. All of the 13 computers (devices) will be able to access the internet at the same time.

简短地回答您的问题：您的网络上可能有成千上万的设备； 理论上。 所有13台计算机(设备)都可以同时访问互联网。

For more information on the practical aspects of tweaking your router and Wi-Fi channels, check out our roundup of previous How-To Geek articles on the topic: .

有关调整路由器和Wi-Fi通道的实际方面的更多信息，请查阅我们之前有关该主题的How-To Geek文章的综述： 。

Have something to add to the explanation? Sound off in the comments. Want to read more answers from other tech-savvy SuperUser contributors? Hit up the original .

有什么补充说明吗？ 在评论中听起来不错。 是否想阅读其他精通SuperUser贡献者的答案？ 点击原始的 。

翻译自:

wi-fi数据双通道