Three Prism Wireless: Wireless network Architecture ramble on

Remember the experiment of sunlight through a prism? The white light passes through the prism and is decomposed into a variety of colors that gradually transition to the color spectrum, followed by red, orange, yellow, green, green, blue, purple, and this is the visible spectrum. It is clear that the prism separates the mixed things.

Today's wireless network is like a bunch of white light, users do not seem to feel the difference at the end, but if the white light through the prism to decompose, you will find that the difference. We will start from the wireless network architecture, to analyze a colorful world.

In fact, the change in the architecture of wireless networks is something that has been brewing. Last year, Motorola Solutions launched the Wing 5 architecture, Aruba launched the move Virtual Enterprise architecture This March, and the Juniper network is integrating smart Mobile architecture into the latest simply Connected solution. For cloud computing, the H3C scheme can be summed up as "AC Cloud and Cloud AC". The network architecture proposed by Cloud is called the cube (unify broadband Evolution). Cisco's Flexconnect architecture provides a wireless network that works when a WAN link is interrupted or AC is not available. Of course, carriers are a very large part of the wireless network, and Huawei's proposed Singleran solution is more skewed towards operators. Some companies do not offer personalized names, but they also offer unique solutions or technologies for the development of wireless architectures.

Behind the Hot wireless network

Obviously, the wireless network has penetrated deeply into our work and life. This was pushed to a new climax at Apple's launch, when Jobs was forced to turn off some Wi-fi because of a concentration of Wi-Fi access points. From a certain point of view, it just confirms the popularity of the wireless network. Of course, in terms of numbers, the hype seems more specific. A recent GSM Alliance report says global mobile connectivity will reach 6 billion, and in a Informa study of the Wireless Broadband Alliance, it predicts that Wi-Fi hotspots will grow by 350% to 5.8 million by 2015.

When a large number of applications access to the network through the wireless access terminals, when the security, management, anti-interference and other needs gradually improve, wireless network in addition to the speed of transmission in a significant increase in the network architecture facing the adjustment is also a natural choice. But where will this adjustment go? What is the extent of the adjustment? Where is the specific impetus?

"Looking back at history, the biggest driver of the FAT AP's transition to the lean AP architecture comes from the user's need for centralized management of large-scale wireless networks and operational dimensions. "Rui Jie Network wireless product director Cai to the original fat thin AP Change reason explanation is many people's consensus." But when it comes to change, it's hard to give that exact answer.

The wireless network architecture you see today does not seem to be in a unified direction. "The wireless network architecture will diversify and the WLAN will have more choices." "Juniper Network China Wireless network system engineer Lin Tao believes that the future of WLAN will be from a single to multiple transformation, and the diversity of WLAN is mainly due to the rich application scenarios." For example, in a simple Soho environment, the FAT AP architecture will continue to dominate, while in the unified management of multiple branches, cloud management architecture will evolve.

Explore the details of wireless network architecture

"Cloud computing + Wireless access + Thin terminal is the inevitable trend of the development of wireless network architecture." "Aruba China Branch president Xu Xian's view of the future is simple and clear. Based on this view, the Aruba move architecture emphasizes more on the security aspects of wireless networks. It unifies wired and wireless into an intranet access solution, and access rights are associated with user identities. This means that, on an identity-based basis, enterprise employees can access network resources consistently and securely without having to think about where they are, what devices they use, or how they connect.

Also bullish on cloud computing, but the details are different, in the H3C wireless product line chief Engineer Miutin is this: "The Future of wireless network architecture, can be summed up as the AC cloud and cloud AC two levels: AC Cloud is a deployment-oriented understanding, cloud AC is a user-oriented business rendering." H3C is about to launch the Mastertm new generation mobile Internet solution based on cloud AC architecture, focusing on realizing and optimizing the general demand of "ubiquitous cloud access" in the aspects of intelligent service perception, 7-layer mobile security defense, real-time spectrum protection, RF optimization and green energy saving. ”

"The distributed architecture of WiNG 5 can bring higher capacity and intelligence." "Motorola Systems (China) Co., Ltd. Wireless network Solutions business General Manager Cai not hesitate to praise the architecture." He said the Wing 5 Wireless LAN solution allows access points to be as intelligent as the controller, where the access points can communicate with each other directly to provide more efficient routing for network services. Data can be transmitted directly from one access point to the next, and each access point is aware of the current state of the network and can find the best routing path under current Network load conditions. Although the controller is still responsible for managing, directing and adjusting the network, it can complete the transmission through the shortest path. The access point has the same intelligence as the controller, which can not only improve the network capacity, but also improve the survivability of the network. The value of this self-healing capability is highlighted when some segment of the network fails. WiNG 5 Wireless LAN access points have network awareness, so you can bypass components that fail or overload to deliver business. At the same time, the access point and controller of WiNG 5 Wireless LAN can detect RF environment intelligently according to user's requirement. This has a very important effect on RF interference, cover notch and overload channel detection.

Cisco Flexconnect architecture allows AP to assume branch backup RADIUS server functionality, through local authentication/distributed client authentication. Both 802.1x and distributed keys are used so that the keys are slow to exist at the wireless access point. Thus, when AC is unavailable, the key is still valid and the wireless client can still authenticate. The Miercom laboratory, which was analyzed in a report this April, allows the branch office to continue working when a WAN link is interrupted or AC is not available. CCKM Fast roaming requires no exchange of keys, even in the case of AC failure.

The simply connected program of Juniper Network, which focuses on simplifying the web, has two concepts: independent of the brand and type of mobile devices and user-centric security and management, and redesign and reduction of network devices in the event of a change in the wired and wireless network's mixed access environment. The Controller integration technology is one of the most important points. It refers to the enterprise deployment of the controller logically grouped into clusters, the management of wireless networks through the cluster to expand. The advantage of this is to achieve a unified configuration that reduces the impact of individual configurations on time and uniformity. Another advantage is that in the AC failure, can stabilize the failover, the AP automatically switch to the cluster in the other controller, the client will not perceive strange.

The Huawei Singleran solution proposed for the operator market adopts a unified base station, unified Base Station controller, unified operation and maintenance management, unified site program, supporting the integration and evolution of different technical systems, so that operators can really from end-to-end operational dimension to consider the network development strategy, the realization of the five core assets " Maximizing the value of spectrum, site, pipeline, user, employee.

The same is the operator's solution, in the proud days of the architecture, the AP as a cube support cloud network element, only responsible for network data forwarding, and not to analyze the data that the use of the strategy to forward, thereby increasing the AP's data forwarding capabilities. The data forwarding strategy is controlled by the cube controller in the cloud, the controller will send the data to support the network element in the cloud, the network element is forwarded according to the policy.

Future-oriented wireless network features

In addition to these separate schema names, many vendors are also trying to adjust to wireless networks. The wireless network itself is also developing.

Security issues have been plagued by wireless networks. However, this situation is also changing. The IEEE 802.11i is a 128-bit or more-bit AES encryption mechanism that no one has breached at the moment. Second, from the user authentication point of view, now many are based on SIM card or 802.1x authentication, this is dynamic key authentication, each key is different, and each packet key is different. So, from this level, Wi-Fi is already very safe. "Ruckus Wireless, China technology director Sun Wenwei, said of security, but he also cautioned that" users cannot ignore the importance of cryptographic management and measure the simplicity of operations and security. ”

High-density deployments have been an emerging problem over the years. The coordinated use of local forwarding and centralized forwarding is a common method to solve this problem at present. Local forwarding is the data by the AP processing independently, without AC, and centralized forwarding mode, the data through AC unified processing. "The use of centralized forwarding alone, the flow of all through AC, there are two hidden dangers, both the formation of performance bottlenecks can easily cause a single point of failure." Of course, the choice of forwarding form is based on the business characteristics of the judge. The use of local forwarding is appropriate for browsing the web and viewing the video. But for some strictly controlled business, such as bank data, is not allowed to forward locally, must flow to the data center, this time to use the centralized forwarding mode. "Sun Wenwei explains this.

Obviously, the intensive deployment of AP will increase the signal interference and cost of input, "The technology of Chinese Cypress's WLAN is completely using sparse AP deployment, achieve accurate positioning, and achieve high-density, large capacity coverage effect (target). Liao Lei, the wireless product manager at Han Pak Technology Center, gives a Hamber solution to this problem.

In China Digital Network wireless product line product Manager Chanlixia, wireless network architecture is not only related to the number of ports, transmission speed and security, and "the integration and application of the Internet of things, so that IPv6 address assignment and wireless operation management become an important function." And on the application of cloud computing in wireless network architecture, digital China Network is mainly through the way of cloud management to achieve AP centralized management. ”

"Management integration, forwarding distribution" is the Cai of wireless network architecture. "Management integration" refers to the wireless network as the core of the centralized controller will slowly integrate into the wired network of equipment at all levels. "Forwarding distribution" refers to the AP will implement local forwarding, AP data need not be controlled by the independent device or integrated machine to centralized forwarding, so as to solve the large-scale AP deployment and large flow applications under the controller performance bottle neck.

From three prisms to a beam of light

Wireless networks are optimized for both the number of ports and the security, disruption, and management capabilities. Each frame or scheme is a spectrum after the prism, but when we integrate the many spectra together, we can see a complete beam of light.

In the light of this "wireless network", it is necessary to remind the user that information is transmitted in the air, so it is unavoidable to encounter disturbances and security problems. Because RF systems are unpredictable, their performance changes as people and objects move. and 802.11n RF media is shared, which means that wireless performance must be affected by the number of users connected. These inherent characteristics seem to cast a shadow over the development of wireless networks, but it is precisely because of the expectations of the future that the development of the entire technology is an inexhaustible driving force. In the same way, users also need to follow the correct process when surveying and deploying to minimize the problem.