Saturday, January 1, 2011

【 Weak current College 】 wireless network devices selection guide 】


Determine the wireless networking standard wireless router AccessPoint is commonly known as AP, shorthand.  In fact, we can understand the wireless router to have broadband access ports, with routing capabilities, wireless connectivity client General router. While the wireless card in functions and traditional network card is only used to transfer data wirelessly. Compatibility for any product is extremely important, the wireless router is no exception. Before selecting a wireless router, you must identify IEEE 802.11b flag.  In fact, the early days of the birth of the wireless device to attach considerable importance to compatibility problems, but for various reasons, some older products are not certified by IEEE and the resulting 802.11b few wireless network card will not work. In General, as long as the wireless router with IEEE 802.11b certification, we can rest assured their compatibility, after all, this is Wi-Fi organizations bring our commitment. In addition to the IEEE 802 .11b standard, we occasionally also see support IEEE 802.11b + or IEEE 802.11g standard wireless network devices.  In theory, the IEEE and IEEE 802.11g 802.11b + than is currently the most popular IEEE 802.11b speed more advantages, but also to be backward compatible, but the price you want. In fact, for home users as well as a variety of small LAN users, IEEE 802.11b 11Mbps bandwidth provided by is sufficient, there is no need to insist on IEEE 802.11b + or IEEE 802.11g. Network connection features some simple broadband router does not have built-in Hub functionality, thus connecting clients is required for Uplink and hub. May surprise everyone expected is that these products are often relatively high-end, able to support many clients share the Internet, but it is not suitable for families, school dormitories, and other small users, because from a cost perspective, broadband router plus hub is very high and occupies a lot of space. In contrast, those 4-port broadband router more worthy of our choice, not only does it deliver Internet sharing feature, you can also make a connection to a LAN connection, and automatically assign IP addresses, but also easy to manage. As for more than 7 port broadband router, excessively high prices may make it difficult to accept, but also practical value.  Before selecting the broadband router, broadband compatibility is what we have to figure out. Generally speaking, the current mainstream products can support ADSL/Cable Modem, ISDN and does not necessarily support. Routing technology on a wide variety of network technologies, we may not know, but at the time of buy a wireless router NAT technology identify DHCP functionality still very necessary, because this is an essential quality of mainstream products. If the products do not see these two points, it is mostly already eliminated the old product, is not worth the purchase. NAT is an internal IP address of the network is mapped into a legitimate IP addresses of Internet technology. When the network is assigned a private IP address and cannot directly access the Internet, the NAT can LAN internal IP addresses into the external IP address of the legitimate for Internet sharing access.  Obviously, if your wireless router does not support NAT technology, so the forum access, online games, and so need public IP of the application, you are helpless. Despite the adoption of a variety of software can implement IP mapping, but this can be quite a hassle, but stability is not high. DHCP function is the dynamic host configuration.  When the wireless router is configured as a DHCP server, it can provide LAN access of each PC is automatically assigned an IP address, but it itself as a DHCP Client and enables WAN ports dynamically obtain the ISP assigned IP address. At this point, users have to do is just the network card in Windows IP specified as automatically gets, and disable all of the gateway and DNS resolution, completely eliminates the hassle of configuring the network for a novice to use. In order to ensure network security, wireless router with firewall functionality is very necessary. Although the hardware firewall cannot block all network viruses, but to prevent hacker attacks or have a certain effect, at the same time can not consume system resources.  As for the FTP server function, users must be on it.  By mapping the 21Port, we can not rely on such erection Serv-U FTP server software to establish your own FTP site, very suitable for multiple use among students in the bedroom. In contrast, a DMZ host, access control, logging, and monitoring capabilities and not very important, because we do not need to monitor and restrict other users, unless you are a wireless router for Internet cafes or large enterprises.  The effective transmission distance for a wireless network device, the effective transmission distance is very important, otherwise the feeling of "influence" will give you trouble. Note that there is no need to refer to the products of "maximum transmission distance", this indicator was in none of the Occluder calculated under the conditions.  Decided to IEEE 802 .11b wireless network transmission range is the key to the wireless router, and wireless network card's relationship is not significant. From a practical perspective, we believe that we should value the wireless router's signal penetration capability, after all the tall buildings of reinforced cement, barrier is the largest block of signals.  For signal penetration capability, the gap between the different products available. Part of the brand-name products can be done within 30 m of the crossing of two wall thick walls, and a few low-end products may have an inability to a small interior "corner" — even if the open door, a wireless router is unable to communicate with another room in the wireless client communication. To resolve this issue, we often see many wireless router uses a dayLine, but this is not the most complete solution to increase the transmission power is the key. As consumers, we are passive, in the purchase will not be able to know that your wireless router's signal penetration capacity and therefore can only be based on the experience of discrimination. In General, the new models in the signal penetration capacity always excellent than the old product, parts support "superposition" of products antenna generally will signal penetration ability as a selling point, this product more suitable to use in a complex environment of the user.  Of course, simply based on the antenna to the wireless router signal penetration ability is not science, many do not use the antenna products but also excellent signal penetration ability. If you have a condition, we can use EMI tester to proposed wireless router startup moments of transmitter power, generally have a greater interference products in signal penetration capacity better. Wireless power and stability for the wireless card, the power and stability is the most important of the two major technical indicators.  On the speed and signal acceptance, currently supports the IEEE 802 .11b standard products do not have too many differences. But if the power is too large or the stability of the poor, so users must be so.  For mobile products, the power consumption has been quite sensitive, if the wireless network connection does not use energy-saving design, laptops, PDAs and other mobile devices for electricity supply would be hard-pressed to seriously affect the actual application. In the choose a wireless network card, it is recommended that you try different brands of products to test their energy consumption.  Many users reflect the tremendous heat wireless card, which is more prominent, especially in summer. From "principle," we should be able to push it, the calorific value of great products will never be energy-saving, and stability of the product, as well as the life is quite negative. Objective, the most famous wireless card quality is very good, when we buycan be focused on Intel, 3Com, Cisco, Linksys, AboveCable products [details please visit our website product library]. For those still using the old model of antenna, most likely because the technology does not cross the border, after all, your wireless router uses the antenna still nothing wrong, and the wireless network card is also dragging long antenna obviously affects portability.

No comments:

Post a Comment