Unified planning and step-by-step implementation
Unified planning and step-by-step implementation "is an important approach that runs through the construction of wireless campus networks in universities. The construction of its wireless network mainly includes wireless signal coverage and
Four parts: networking, wireless testing, wireless network management, and wireless applications. The construction of wireless campus networks is essentially a form of network infrastructure construction, despite the development of WLAN
Not long ago, commercial applications have just begun, but over the past few decades, with the development and maturity of wired networks, concepts such as network construction, network management, and network maintenance have become deeply ingrained
Entering people's hearts, the construction of wireless networks also includes these basic contents. In addition, due to the fact that the transmission medium of WLAN is radio waves, it also has characteristics different from wired networks
Due to its convenience and flexibility, the construction of wireless campus networks also includes testing of wireless signal coverage effectiveness, wireless network security, and typical applications of wireless networks
WLAN specific content. 
Wireless network independent network
Wireless campus network, as an important network infrastructure, is inevitably one of the important components of the basic construction of new campuses. However, the deployment of wireless campus networks is not
Our wireless networking principle is "wireless independent networking", which means that APs should be connected to wireless dedicated switches as much as possible on physical links, without any logical topology issues
Try to assign lines to a separate VLAN, so that the wireless campus network becomes a parallel network to the wired campus network. This design principle facilitates centralized management of wireless devices, making it convenient
Implementing network management strategies specific to certain wireless networks and facilitating the implementation of certain special applications of wireless networks.
Of course, in the deployment of wireless networks in some old buildings, the original cabling system and allocation of network equipment did not take into account the construction of wireless networks, resulting in physical links
It is also difficult to equip wireless devices with separate switches and network links. We can only implement the principle of wireless independent network formation based on logical topology, which requires attention to Lou Yuyuan
Some wired network configurations require significant modifications, which can be quite labor-intensive, but we believe it is worth it in the long run.
In the specific implementation of wireless networking projects, due to the lack of mature theories and tools for the planning, design, and implementation of large-scale WLAN networks. We are considering in Ming
After there is a need to cover WLAN hotspots, it is necessary to conduct preliminary research on the hotspot situation, including: (1) reviewing the architectural drawings related to the hotspot and analyzing the hotspots
Conduct on-site inspections to understand the coverage area of hotspots, building structural characteristics, and certain environmental factors that may affect WLAN deployment; (2) There is no research using this hotspot
Types, quantities, and network resource access requirements of online network users. After collecting hot topic related information through research and combining the characteristics of various wireless signal coverage technologies,
Suitable coverage methods can be selected for hotspots to implement coverage. 
Based on the specific characteristics of the hotspot environment, the following coverage methods were used.
Pure AP multi cellular coverage
This method is based solely on the idea of "increasing the number of APs", which achieves the goal of wide range wireless RF signal coverage by using multiple APs. We can incorporate a certain requirement
To achieve wireless signal coverage, a large area should be divided into multiple smaller areas, which can be achieved using a single AP
Covered. Pure AP multi cellular coverage is relatively simple and fast to implement, but it has the following disadvantages: (1) it is easily limited by WLAN high frequency and low power, and can cover indoors
The diversity and complexity of architectural patterns can also have a significant impact on the effectiveness of AP signal coverage; (2) As is well known, the current mainstream 802.11b/g APs are
There are only three completely non overlapping frequency points within the frequency range of 2.4-2.4835GHz. If the frequency points of adjacent APs cannot be staggered, same frequency interference will occur. When the interference is severe
This will affect normal data communication.
Covering from outside to inside
This method is a special application of AP multi cellular coverage. When a building structure is a regular "tube shaped building", the AP can be installed outside the building from both sides of the building
Covering the building through the windows of the rooms, using this method, each AP can cover multiple rooms on multiple floors, so that only a few APs are needed to achieve the desired effect
The purpose is to cover the entire building. When there are not many users, this method can be a convenient and low-cost deployment method.
WLAN+GSM combined coverage
This method is first based on a combination of two design ideas: "extending the coverage range of a single AP signal" and "increasing the number of APs". In addition, the important features of this method are:
Extend the coverage range of a single AP signal using an antenna feeder system that meets the requirements of WLAN+GSM combination. The antenna feeder system is an important component in the field of mobile communication
With the continuous development of wireless local area networks, some concepts that were originally in the field of user mobile communication have gradually been transplanted into wireless local area networks.
The WLAN+GSM combined antenna system "refers to the use of multi frequency antennas, multi frequency power dividers, couplers, and other components in the antenna system to enable the integration of GSM and WLAN networks
Wireless signals can be transmitted through a set of antenna systems. One of the advantages of this method is that it can not only support WLAN, but also solve the problems that exist in other mobile communication systems
Indoor coverage issues can reduce investment costs and construction difficulties, accelerate project progress, facilitate system maintenance, and be beneficial for operators to carry out comprehensive wireless services. In addition,
One of the advantages of the antenna feeder system is that it can overcome the impact of the complexity of indoor building layout on wireless signal coverage. In large-scale indoor coverage, wireless signals can
More evenly distributed.
Single WLAN antenna coverage
The so-called pure WLAN antenna coverage is proposed relative to the combined coverage of GSM+WLAN. This coverage method refers to the wireless transmission of only APs in the antenna feeder system
Therefore, the construction of the antenna feeder system in this coverage method can also be designed based solely on the transmission of 2.4GHz WLAN signals. In practical applications, when the building environment is complex
When the conditions for combining with GSM are not met, it is possible to consider using the antenna feeder system solely for WLAN. 
Wireless network user management
There are a large number of outsiders active on campus every day, and many of them have a need for mobile work; At the same time, our school also has a large number of non experts in computer technology
How to configure complex client software for humanities teachers who are often proficient in using 802.1x authentication method will become a difficult task to complete
After weighing various pros and cons, deploying web-based wireless authentication has become our ultimate choice.
For the issue of how to configure VLANs, we have chosen to configure a unified VLAN. The advantages of doing this are obvious, a unified VLAN is easier to manage, and it's not a problem
VLAN, which is equivalent to a wired network, logically establishes an independent network. Based on this, adopt a unified security policy, authentication method, and access
The control is very convenient, and any modifications made to this VLAN will only affect the users of this VLAN, not the wired network users. Another special advantage
It is possible to establish an association between a username and a specific IP address, so that users can access the internet wirelessly in any hotspot area of the school
Same IP address. We only need to configure one DHCP server in this VLAN.
Of course, this choice also has its drawbacks. On the one hand, we need to reconfigure the networks in all hotspot areas, as we need to use networks that are different from wired networks
A separate VLAN requires configuring Trunk for the switch, which would require reconfiguring each port on the switch, resulting in a significant workload; On the other hand, if all
If all wireless networks are configured with the same VLAN, there may be many hosts in the same VLAN. Once a machine is infected, scanning the entire VLAN may affect other hosts
Machine.
Taking into account the pros and cons of various factors, our final certification method is to use public areas on campus where students and teachers are concentrated, such as public green spaces, classrooms, canteens, etc
Use a unified VLAN and perform security authentication using web authentication. If there are higher requirements for data communication security, an additional three layers can be used
VPN dial-up. In some special locations, such as school offices, party offices, academic affairs offices, finance offices, and other key departments, they can independently use the same VLAN configuration as wired networks
Implement 802.1x authentication as needed to increase communication security. 
Improve management and application level
In the construction of wireless campus networks, network management also plays an important role. From the perspective of device management, it is necessary to determine the placement location and configuration parameters for various wireless devices
Detailed recording and management of numerical information. From a security management perspective, it is necessary to have methods and capabilities to detect and quickly handle counterfeit APs and wireless DOS attacks. from
From the perspective of performance management, it is necessary to fully understand and analyze some specific performance indicators of wireless networks, such as channel signal strength/quality, network real-time performance -
Throughput, traffic of each AP, etc.
A good network requires good management. Potential faults should be detected before network failures occur, and timely measures should be taken before users notice them
Reason.
Currently, wireless campus networks in universities have been used to serve teaching, administrative, and research purposes due to their convenience and flexibility, which are different from wired networks. But we should also be clear headed
It is recognized that the development of wireless networks, like the initial development of wired networks, requires some critical applications to run on the network, and applications are the key to the development of wireless networks
The maximum power. For example, wireless networks can also serve as link backups for wired networks, bearing some network traffic in the event of network failures or congestion
In addition, applications such as VoIP, live streaming, and video surveillance are all potential drivers of wireless network development, and we will gradually expand them in the construction process.