Analysis of key issues in establishing a wireless LAN

Wireless networks are becoming the focus of pursuit with their "Ubiquitous" charm. Whether it is network upgrade or network re-networking, people always hope that their networks can get rid of the limitations of cables and enter the free world. However, compared with wired products, wireless products are still new, and not all users can grasp the key points of the establishment. Here, we have collected six general questions to answer, hoping to help you build a WLAN.

Is it 802.11g or 802.11b?

Currently, there are three ways to achieve wireless Internet access: WLAN wireless Internet access, CDMA Internet access, and GPRS internet access. For domestic users, WLAN wireless Internet access is an excellent solution to experience wireless freedom, regardless of speed or cost. Currently, products that can build WLAN networks on the market can be divided into 11 M, 54 M, 22 M, and Micron M according to their different rates. In the past, the two products were the most common. Which of the two standards is more suitable for family users?

It is not easy to answer this question, because although the 802.11g product can be regarded as an upgrade of the 802.11b product, the advantages in compatibility, stability, coverage, and price are not obvious. First, the 11 m transmission speed of 802.11b is higher than the access speed of Common Household broadband types such as DSL and LAN, which can fully meet the needs of domestic users for wireless broadband Internet sharing.

Second, the price of 802.11b products is easy to accept. From the current price point of view, the same brand of 802.11g products are often two ~ Three times, but a few vendors have recently lowered their prices to a level acceptable to users. There are also many 802.11b products that have passed the test of the market, and there are many choices, so it is more suitable for family users.

802.11g is the mainstream of future development. However, we need to remind you that when 802.11g products and 802.11b products are used together, the throughput can only reach about mb. Therefore, 802.11g products are more suitable for the formation of new networks.

Do I need to purchase a wireless firewall separately?

Network security is an eternal topic, but it is especially heavy in wireless networks. We will not go into details about the security vulnerabilities of 802.11x. The question we want to answer is: Do I need to purchase a wireless firewall to build a wireless network?

In the wireless field, there are not many products dedicated to firewall functions, even if there are, home users cannot afford the cost. In other words, wireless firewalls are always bundled with other products and appear as an additional feature of other products. The most common feature is wireless broadband routers.

A Wireless Broadband Router is a product that is more cost-effective than a Wireless AP. It is currently the best product for achieving home network sharing. The price of household products is 500 ~ Between 1000 yuan, during the summer promotions, their prices have been greatly reduced. These products generally integrate AP, routing, and switch functions. Some products also adopt advanced Stateful Packet Inspection firewall technology to defend against DoS attacks, you can also send a warning to E-mail that may be faulty. In addition, many products also have a variety of security measures, such as 128-bit WEP encryption, SSID hiding, and MAC address filtering. MAC address filtering is a common security solution for small-scale networks. It checks the source MAC address of user data packets to authenticate the user's credibility. For advanced users, you can also establish a dedicated Security channel through the VPN function.

To ensure the security of wireless networks, firewall is necessary, but there is no need to purchase additional firewalls for home users. The firewalls and related security measures provided by wireless routers can meet the requirements. Although this hardware firewall cannot block all network viruses, it still has some effect on preventing hacker attacks without occupying system resources. Finally, we need to remind you that traditional software firewalls and anti-virus software can also play a good role in security defense in wireless networks.

Is the wireless Nic a USB interface or a PCI interface?

Wireless NICs are divided into three types based on different interface types: PCMCIA wireless Nic, PCI wireless Nic, and USB wireless Nic. The PCMCIA wireless Nic can only be used for laptops, and the latter two can be used for desktops.

PCI wireless NICs are designed for desktops Using PCI slots. They can directly exchange data with the computer memory independently of the host CPU, reducing the CPU burden.

However, its disadvantage is also obvious, mainly because the signal receiving position is not adjustable, it is vulnerable to interference from the computer host, and it is easy to lose the line. Wireless NICs using USB interfaces not only have the advantages of plug-and-play, strong thermal performance, and fast transmission speed, but also can conveniently use USB extended cables to keep the NICS away from the computer, avoid interference and adjust the network card position and direction at any time. Its disadvantage is that it is not easy to manage and the price is relatively low.

From the above analysis, we can see that unless your motherboard does not support USB interfaces, you should give priority to USB wireless NICs, and the price is generally acceptable, for example, the TP-Link WN230 USB wireless network card only costs 290 yuan. If you have a large number of USB devices, you can use the "one-to-four" USB adapter.

Is the wireless package a chicken rib?

From the recent promotions, various wireless suits are the most dazzling. From the merchant's point of view, this product is mainly for junior users and aims to expand their market share. In addition, it has certain guiding significance for consumers in terms of product compatibility and matching. In addition, there are also obvious discounts. But from the consumer's point of view, this is not necessarily so cheap. A friend of the author has long been using wireless networks in the Organization due to work needs. Recently, he wants to build a wireless network at home. Although the wireless package is very cost-effective, he already has a PCMCIA wireless network card and only needs a wireless router. If he buys the entire suit, he thinks it is not cost-effective; if he buys a single suit, the "huge" gap in price is unacceptable.

However, it should be emphasized that each product has its own market position, and the wireless package mainly targets beginner users who are "one man, one man, two white. Those consumers who already have a certain level of Foundation want to buy a wireless package, although it is inconvenient, it is not necessarily a waste of money. There is a way to learn from it: Find a "like-minded" friend in the market and buy a wireless package together. Leave contact information before breaking up to take care of each other during the warranty period. In this way, we both enjoyed the preferential policy and bought satisfactory products, while adding a "circle" friend.

Do I need to purchase an antenna?

There is no end to the requirement for wireless transmission distance. We also know that the "maximum transmission distance" in the product introduction is mostly calculated without any obstruction, in actual use, it cannot be reached. Do we need to purchase an antenna?

First, we should be clear that both wireless NICs, Wireless AP, and wireless routers have built-in wireless antennas. When the transmission distance is close, generally 20 ~ 30 meters, outdoor 50 ~ 100 meters, there is no need to purchase an external antenna. Secondly, the effective wireless transmission distance is also related to the signal penetration capability, and the gap between different products is also very large. Generally, brand-name products can traverse two walls within 30 meters, and a few low-end products may lose line at a turning point. In addition, the key to determining the wireless network transmission range is the AP or wireless router, which has little to do with the wireless network card.

From the above analysis, we can see that for domestic users, it is necessary to consider outsourcing gain antennas only when long-distance data transmission is required, and there is no need to purchase additional antennas for household short-distance transmission. If the seller repeatedly states that the failure to configure an external antenna will affect normal transmission of the product, we have reason to question the quality of the product.

Do mature products also need to focus on brands?

Relatively speaking, 802.11b is a relatively mature technology. There are many products on the market that support it, and the price is very attractive. Can we ignore the brand and value the price?

This seems a bit old-fashioned, but our intention to trust the brand is not limited to the product itself, which requires buyers to look at wireless products in the long run.

First of all, the speed and signal acceptance capabilities are similar to most of the products currently supporting the 802.11b standard, but the power consumption and stability are quite different. Famous brand manufacturers will use genuine brand-name Wireless chips and electronic components, reliable quality, stable performance. In some small factories, low-end or even defective wireless chips are used. As a result, the product power is too high or too small. If the power is too small, the signal coverage and transmission stability of the wireless network are poor. If the power is too large, it will adversely affect the human body. If it is a PCMCIA card, the wireless freedom of the notebook is even worse.

Secondly, wireless products are constantly evolving products. Only those large factories are able to provide users with Upgrade solutions in a timely manner, and small factories will not be able to provide such services.

It should be noted that, although there are many products that support the 802.11x standard, they are still not very standard, and the products of various manufacturers still need to be further improved in terms of mutual compatibility. At the same time, manufacturers have created too many technical terms to highlight their own characteristics, and ordinary users have no energy to analyze them. Therefore, if you want your wireless network to be scaled up and upgraded in a timely manner, select a famous brand product. Wireless networks are becoming the focus of pursuit with their "Ubiquitous" charm. Whether it is network upgrade or network re-networking, people always hope that their networks can get rid of the limitations of cables and enter the free world. However, compared with wired products, wireless products are still new, and not all users can grasp the key points of the establishment. Here, we have collected six general questions to answer, hoping to help you build a WLAN.

1. Establish a Secure and Efficient wireless LAN on three sides
2. Wireless LAN system creation instance