Office networking for wireless network applications

In the face of the rapid development of wireless networks, how should we set up the network in the office? The choice of hardware equipment, cost control, and later maintenance require the consideration of network administrators.

Office networking 1. device Selection

The device contains many factors such as brand, price, performance, and positioning. Here we will give you a brief introduction. Currently, the main brands of wireless routers include network devices, Belkin, D-Link, TP-Link, Buffalo, H3C, and Cisco. The price also ranges from several hundred yuan to several thousand yuan. It is recommended that enterprise users choose products launched by various brands for enterprise users. In terms of product performance, 802.11g-based wireless router products are currently a good choice, because 802.11n-based products are not yet mature, and the compatibility of each product is also different from previous tests, in addition, the network card of the client cannot be unified, and the price of the 802.11n-based wireless router and network card is very expensive. Choosing a device doesn't necessarily only look at the brand, as long as it suits your enterprise's application needs.

Office networking 2. Control Costs

For an enterprise, how to control investment costs and get a good Roi is a matter of great importance to every boss. When selecting a device, you should select the product type and quantity according to your actual environment in advance. For example, if an office area is scattered and there are many obstacles in the office environment, we should select a router with strong signal penetration capability.

Office networking 3. Post-Maintenance

After selecting a product, the user also needs to consider factors such as after-sales service of the product, such as the service and firmware upgrade after the fault occurs, it is even necessary to consider the recoverability and recovery time of the entire network after the attack.

Recommendation of Wireless LAN Solutions in three network environments

After briefly introducing the technologies and indicators of wireless products, we will introduce some applications of the three types of wireless products in the actual environment. Wireless products usually work in the following states based on different application scenarios:

1. AP Wireless Access Point (signal coverage mode) and AP Client (wireless Client mode ).

2. WDS Wireless Distributed System (bridging mode) and AP + WDS hybrid mode (both bridging and overwriting ).

3.802.1x authentication and seamless client roaming.

802.1x Authentication and seamless client roaming

This solution is applicable to a wide range of public places such as large enterprises, airports, bars, and hotels. This enables high-density, high-speed wireless access, mobile Internet (roaming), 802.1x authentication, and billing.

We recommend that you ask the device manufacturer to make a good design plan and budget before using the service. You may also want to refer to several successful cases. At that time, we believe it will be helpful for your enterprise's wireless network solution construction.

In recent years, more and more products have been added to the wireless family. Laptops, mobile phones, cameras, projectors, and other devices have become one of the indispensable office and communication devices. We often see some SOHO users who are using laptops to wirelessly access the Internet at the entrance of the cafe, and business users who use PDA to download emails. It is precisely because of its high mobility that many people rely more on wireless Internet access. In addition, the use of wireless networks is also one of the information exchange methods used by small and medium-sized enterprises. However, setting up an office wireless device is not as simple as we think. Buying some equipment is just as simple as assembling it. It contains many factors before the establishment of the office LAN, the main problems include the coverage of office wireless signals, the security of wireless networks, and the compatibility of wireless devices. Today, we will discuss with you how to implement the wireless network environment in the office.

Coverage of wireless signals

Just now we have talked about the advantages of using wireless networks. Below we will also talk about some of its shortcomings. First, the signal coverage of wireless networks is one of the factors we need to consider. When it comes to signal coverage, we should first look at its transmission protocol. Common wireless network protocols include IEEE 802.11, IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, and the draft standard 802.11n. Although IEEE 802.11 \ 802.11a has been eliminated by new standards, it is undeniable that the first wireless LAN standard proposed by the Institute of Electrical and Electronics Engineers in 1997 is a milestone in the development of IEEE 802.11 wireless network technology.

Standard operating frequency transmission speed remarks

802.11a 5Ghz54Mbps non-mainstream technology fast speed compatibility poor price high

802.11b 2.4Ghz11Mbps mainstream technology, slow speed, good compatibility, low price

802.11g 2.4 Ghz/5Ghz54Mbps mainstream technology fast speed, good compatibility, low price

802.11n (draft) 2.4 Ghz/5.8Ghz300Mbps future technical speed fast compatibility low price high

Misunderstanding 1. The stronger the signal, the better.

First, let's take a look at several hardware metrics of wireless products: transmit power, accept sensitivity, and antenna gain. At present, the main trend of wireless networks is in signal coverage and transmission rate. Generally, the method to enhance the signal is to increase the transmission power and enhance the antenna gain.

Transmit power: wireless devices use the transmit power to measure the transmission signal performance. The larger the transmit power, the longer the transmission distance between wireless products, the wider the coverage, and the stronger the penetration capability. The unit of measurement for transmit power is dbm. This is roughly the same as the light bulb that we use in our lives. The larger the wattage, the brighter the bulb, and the wider the illumination range.

Gain: The gain refers to the enhancement of the signal transmitting and receiving capabilities of the antenna. The larger the gain, the stronger the signal transmitting capability and the higher the sensitivity. The gain measurement unit is dbi. The antenna size and internal materials have a great relationship with the antenna gain.

Why is the stronger the signal, the better? The reason is that the signal is too strong, so the range is larger, the controllable area is reduced, and the security of users is reduced. For example, although a user can receive signals in a unit with an area of more than 300 square meters in the office area, his security is not the best.

Misunderstanding 2 the higher the standard, the better

In wireless products, products based on the 802.11n draft standards are currently the most advanced technology, with far-reaching signal coverage. This is precisely because many enterprises tend to pursue hardware indicators too much when purchasing equipment, while ignoring the ease of use and price of products. According to the current prices of some 11n products sold in the market, the prices of most router products are between-yuan, while the prices of 11n-based wireless NICs are between-yuan. What is the concept of such a price? Currently, the price of 802.11g-based wireless routers sold in the market is around 200, and the price of 11G wireless network cards is around 150 yuan. In comparison, the price of 11n products is 7-8 times that of 11G products. Although 11N products are leading in technology, we do not recommend small and medium enterprises because of immature prices and technologies. Compared with 11g products, 11N products are more suitable for small and medium enterprises.

Set up Wireless Network Security

Unauthorized users

We know that wireless signals are transmitted in the air. As long as the signals are covered, some illegal users can obtain wireless network data without any physical connection. Therefore, it is necessary to prevent illegal terminal access and data leakage from multiple aspects.

The solution is to use authentication to prevent unauthorized user access. In other words, it is to use various encryption methods to prevent illegal user intrusion. Binding a MAC address is the most common and simplest method. Each wireless network card has a unique MAC address, which is encrypted by binding the AP settings to the MAC address of the NIC, however, this security method applies to family users who do not have high requirements on information. For enterprise users, we recommend using two common encryption methods: WEP and WPA.

Illegal AP access

In addition to threats to the security of the wireless LAN, unauthorized AP access also threatens the entire network. When a Wireless AP is connected to a wired hub, an illegal AP attack occurs. An illegal AP installation may damage valuable resources of the wireless network.

The solution can be prevented by verifying the validity of the AP and regular site reviews. During this verification, not only does the AP need to confirm the legality of the wireless user, the wireless device must also verify whether the AP is a false access point before communication.

Virus and hacker attacks

Apart from the above two points, viruses and hacker attacks also pose a threat to the wireless LAN. Many networks have a set of well-configured security devices as the network shells to prevent illegal attacks, however, the network protected by the shell is very fragile and vulnerable to attacks. Hackers can quickly access the network trunk through simple configuration, so that the network is exposed to attackers. Therefore, preventive measures must be strengthened. Even a network with a certain number of border security devices can expose the network to be attacked.

A common solution is to install a firewall, install and upgrade the client, and install anti-virus software. In addition, the company's wireless network must be isolated from the core network.

Service and performance restrictions

We know that the current wireless LAN transmission bandwidth is limited, which is far from enough compared with the wired network. In actual use, due to the overhead of the physical layer, the actual throughput is only half of the standard, and the actual throughput is shared by all users. If hackers send a large number of ping requests from the Ethernet, the bandwidth of the AP will be saturated. If broadcast traffic is sent, multiple APS will be blocked at the same time, attackers can send signals in the same wireless channel of the same wireless network, so that the attacked network will automatically adapt to the attacks through the CSMA/CA mechanism, which also affects the transmission of wireless networks. In addition, transmission of large data files or complex client/server systems will generate a large amount of network traffic.

To solve this problem, we often conduct network monitoring. If the AP quality and Signal status are unstable, we recommend that you use a tester or other equipment to detect the AP. This can effectively identify the network rate and frame type, help locate faults.