WOT Boco Nie Xiaoyun: WLAN network capacity performance design and optimization

[51CTO.com original article] Just last week, the WOTA Global Architecture and Operation Technology Summit hosted by 51CTO was grandly held at the Beijing Renaissance Hotel. This WOTA set up 15 cutting-edge hot technology forums, and 60+ technical experts from first-tier Internet companies at home and abroad such as Google, LinkedIn, Airbnb, Baidu, Alibaba, and Tencent will bring more than 50 practical architecture experiences and successful experience sharing cases, and work together to create a two-day industry-leading technology event.

On the afternoon of the second day of the conference, at the D conference hall with the theme of "Network Performance Optimization Practice", Nie Xiaoyun, technical manager of the network access product department of Brocade, gave a wonderful speech on the theme of "WLAN network capacity performance design and optimization". After the meeting, the reporter interviewed him and asked him to share his experience in WLAN network capacity performance design and optimization.

The Evolution of WiFi

Over the years of wireless network development in China, its network performance, access terminals, and user needs have undergone tremendous changes. Nie Xiaoyun summarized these changes into three points:

First, the bandwidth of wireless networks is getting larger and larger. From browsing the web, to sending and receiving emails, to today's video transmission, users' demand for wireless network bandwidth is becoming more and more obvious.

Second, there are more and more access terminals, and the terminal density of WIFI itself is getting higher and higher.

Third, there is an increasing emphasis on application security, with many users considering security as a key consideration.

How to avoid WiFi interference?

Although the performance of WiFi has been greatly improved, it often encounters poor user experience during use. Nie Xiaoyun believes that one of the main reasons affecting user experience is WiFi interference. He told reporters that usually, different terminals, AP performance, different distances from terminals to APs, and different numbers of access networks have a great impact on Wi-Fi performance.

In addition, there is interference from the WiFi system itself, and interference from the wired and wireless network architecture. He further explained that since the wireless spectrum is limited, if the AP deployment location and channel selection are isolated, mutual interference will be relatively low, but vice versa, it will greatly affect WiFi performance. The interference between wired and wireless is also very easy to understand. First, the performance is limited by the processing power of the AC itself. Second, if the wired switch is designed according to the traditional wired concept and no relevant performance optimization is done, the wired and wireless cannot be deeply integrated, which will seriously affect the user's functional experience.

Treat WLAN system capacity design like painting

When speaking at the conference, Nie Xiaoyun used two very vivid pictures to explain to the audience the importance of wireless network system capacity design.

He told reporters that there is isolation between wireless channels, just like a palette. When designing a WiFi network, APs need to be deployed in different colors within the coverage area that users want to cover, so that the overall wireless performance is like a painting, with clear layers. If customers can do this, the performance of WiFi is basically guaranteed, and there is less interference and overlap between them.

However, if the entire layout is not set up at the beginning of the design, it will be like an impressionist painting, with random colors and no clear boundaries. It will be a very painful process to optimize it afterwards. "WiFi design is similar to painting. When looking at a WiFi coverage scenario, you need to consider the architecture first: where are the high-density user areas? Where are the low-density areas? Where are the interference areas? At this time, there are different refractions for different channels. After planning, you find that the WiFi you designed is like a clear-colored painting, which means you are halfway to success." Nie Xiaoyun concluded.

Safety must always be there

With the exposure of CCTV 315 for two consecutive years, the security of WiFi has been questioned. Nie Xiaoyun said that when WiFi technology was first designed, not many security issues were considered, and there were indeed system vulnerabilities. After the 802.11i/802.11w and especially Hotspot2.0 specifications came out, the security of the WiFi system was greatly improved from the principle design level, and from the protocol technology and technology, it can fully meet the needs of anti-eavesdropping and anti-fake AP.

Of course, the improvement of technology alone cannot solve all security problems. In real life and work, different implementation scenarios have different deployment and commercial requirements, and there are often deviations in the implementation of security performance. A long time ago, Brocade considered the security requirements of public hotspots, including those of enterprises, and proposed the concept of secure hotspots. A secure hotspot means that in public places, users can enter an open network, but only register. After the registration is completed, once the identity is authorized, they can quickly switch to a secure SSID. SSID uses encryption technology, and the encryption key can be distributed according to different users. This DPSK technology is a unique security technology of Brocade.

At the end of the interview, the reporter asked Nie Xiaoyun how he viewed the future of 5G technology and WiFi technology, and whether there is a conflict between the two. Nie Xiaoyun believes that WiFi itself has a wide spectrum and can provide the lowest cost per unit, whether it is the cost of equipment, the cost of construction and maintenance, or the subsequent security or management costs of users. Therefore, even for telecom operators, they provide wireless services to enterprises. It is the most economical and efficient to adopt the WiFi model. Moreover, WIFI is still developing. For example, 802.11ax can provide a transmission rate of more than 10Gbps. The bandwidth spectrum efficiency will become higher and higher, and the application will become more and more extensive. It has been applied to other fields besides broadband wireless access, such as location-based services, IOT device interconnection, smart home, wireless city, etc. Regardless of the operator level, voice, data or video can be transmitted on the WiFi network. Not only that, WIFI, as a technology that can fully independently implement the security strategy, user management strategy, and system maintenance required by customers, is still in an irreplaceable position.

"I believe that for a long time in the future, WiFi and 5G will remain in a state of interdependence and coexistence," Nie Xiaoyun said firmly.

[51CTO original article, please indicate the original author and source as 51CTO.com when reprinting on partner sites]