In terms of transmission rate, 802.11n can increase the transmission rate of WLAN from 54 Mbps provided by 802.11a and 802.11g to 600 Mbps or even up to Mbps. The mimo ofdm technology applied in combination with the multi-input and multi-output MIMO) and OFDM orthogonal frequency division multiplexing technology improves the wireless transmission quality and transmission rate. The existing 802.11n Wireless AP/routing devices are mainly M and M products. These two products are highly practical and cost-effective. According to the 802.11n scheme, a single antenna product can only be a m product. Only dual/three antennas or more can achieve a higher speed. The existing 802.11n wireless NICs are mainly m mobile phones), m mainstream laptops), and m Apple laptops ). The usage frequency is GB for all devices) and 5 GB for a small number of mobile phones and most Apple devices ). Although the nominal data of 802.11n is large and the maximum theoretical value reaches 600 M, it is not possible to reach this speed due to channel pollution, various types of interference and blocking. Due to the popularity of Apple devices, 5G wireless network cards are installed in the latest MBP/MBA/IPAD, so 5G users are also quite impressive. At the same time, in newer Windows laptops, dual-band wireless network adapters are also increasingly used. This test mainly verifies the specific performance of wireless transmission under 2G and 5g. The output conclusions serve as a reference for the future use of wireless devices. In this test, four devices are used:
| PC |
Dell E6400 |
| PC |
MBP A1278 |
| Wireless Router |
EA4500 |
| Wireless USB Nic |
D-Link DWA-160 Xtreme N Dual Band USB Adapter (rev. B2) |
Cisco EA4500 is a 450 M + 450 M, dual-band 2.4G + 5G) wireless routing product, wired port is 5 Gigabit, it is currently Cisco's highest-end wireless routing product. It is equipped with six built-in antennas, of which 3 are used for 2G and 5g respectively. The biggest feature is that there is no China Bank, the warranty is only one year, and cannot be implemented in China, no invoice .....
650) this. width = 650; "alt =" "src =" http://www.bkjia.com/uploads/allimg/131227/0141403549-0.png "/> this figure clearly shows the differences in the current Cisco linksys product line. The last three types of interfaces supporting Cisco Connect Cloud have few fancy functions. You need to use a specific firmware to perform the operations very well when the Internet speed is poor and the machine configuration is poor. This feature is a very unpleasant feature, so it is discarded .) 650) this. width = 650; "alt =" "src =" http://www.bkjia.com/uploads/allimg/131227/0141404052-1.png "/> function is basically described above, with a USB port, supports DLNA for video and audio servers. The test environment is based on two mainstream laptops, Dell's E6400 and Apple's 13-inch MBP A1278. The E6400 uses an external USB wireless network card: Dlink dual-band DWA160 wireless network card, and the BNS uses its own ipvm broadcasted dual-band wireless network card. Both laptops are Gigabit wired NICs. The specific configurations of the two devices are as follows. This apple is complacent with a gb ssd, and the price is quite pleasant. It is essential to install B in silk.
| Model |
Dell E6400 |
Apple MBP A1278 |
| CPU |
Mobile DualCore Intel Core 2 Duo T9600, 1600 MHz (6x267) |
DualCore Intel Core i7 2620 M, 3400 MHz (34x100) |
| Memory |
4G DDR2-800 |
4G DDR3-1333 |
| Wired Nic |
Intel (R) 82567LM Gigabit Network Connection |
Broadcom NetXtremeBCM57765 Gigabit Ethernet |
| Graphics card |
NVIDIA Quadro NVS 160 M (256 MB) |
Intel (R) HD Graphics Family (1854840 KB) |
| Wireless Network Card |
D-Link DWA-160 Xtreme N Dual Band USB Adapter (rev. B2) |
Broadcom BCM4331 802.11N Wireless Network Adapter |
| Hard Disk |
Hitachi hts725032a9a450ata Device (298 GB, IDE) |
Apple ssd TS512C ATA Device (465 GB, IDE) |
IxChariot5.4 is used for testing, and High_Performance_Throughput.scr is used for the following tests: wired → wired; wired → 2.4G; wired → 5G; 2.4G → 5G. Because the purpose is only to test the trend of 2G and 5g transmission speed, and not to test the signal strength, no tests are conducted for multiple points. Considering the theory of fast attenuation of high-frequency signals, 5g signals passing through the wall are also known in advance. In particular, the latest release of 802.11ac has even worse wall penetration performance, but the speed is faster. It can be said that in terms of speed and wall penetration, the user can only choose one of the most suitable ones. Because the test software IxChariot requires Windows XP, and the Windows XP system cannot be installed on the MBP, a clean windows xp system is installed on the MBP using VMware Fusion and a test platform is deployed.
| Test Environment |
IP |
Nic |
| E6400 real machine XP) |
172.16.200.120 |
1g wired) |
| Apple Virtual Machine XP) |
172.16.200.149 |
450M2. 4/5G), 1G wired) |
| EA4500 wireless route |
172.16.200.1 |
450 M + 450 M + 5*1G |
| DWA-160 wireless network card) |
172.16.200.115 |
300M2. 4/5G ), |
|
| Software |
Version |
|
| IxChariot |
5.4 |
|
| Supporting Endpint |
6.3 |
|
Test wired → wired first use a network cable to connect two laptops to EA4500 for a performance test to verify whether there is a bottleneck in the transmission between the VM and the real machine. 650) this. width = 650; "alt =" "src =" http://www.bkjia.com/uploads/allimg/131227/0141405Z0-2.gif "/> 650) this. width = 650;" alt = "" src =" http://www.bkjia.com/uploads/allimg/131227/0141404N1-3.png "/> When 10 threads are enabled, the average final transmission result is 900 MB. Although the maximum transmission value is lower than that of the 1g Nic, the virtual machine may have a certain performance loss. However, this value is far greater than the theoretical maximum value of the wireless network card and does not affect subsequent tests. Wired → 5G 650) this. width = 650; "alt =" "src =" http://www.bkjia.com/uploads/allimg/131227/01414063P-4.gif "/> 650) this. width = 650;" alt = "" src =" http://www.bkjia.com/uploads/allimg/131227/0141405350-5.png "/> Enable 20 threads and connect 5g with the E6400 Gigabit Nic using the MBP. We can see that the average final transfer result is 234 M, which is a good value. Wired → 5G-2650) this. width = 650; "alt =" "src =" http://www.bkjia.com/uploads/allimg/131227/01414055P-6.gif "/> 650) this. width = 650;" alt = "" src =" http://www.bkjia.com/uploads/allimg/131227/01414044M-7.png "/> Enable 14 threads and use the DWA-160 on the E6400 5G band to communicate with the gigabit network card of MBP, the average value of 140 M, because the maximum speed of this network card is 300 M, less than the 450 M, the speed is slower than expected. Wired → 2.4G650) this. width = 650; "alt =" "src =" http://www.bkjia.com/uploads/allimg/131227/014140H13-8.png "/> 650) this. width = 650;" alt = "" src =" http://www.bkjia.com/uploads/allimg/131227/0141402363-9.png "/> Enable one thread to enable the connection between the MPO wired network card and the Dell E6400E DWA160 2.4G band. Average: 67.62 M. We can find that the speed difference between 2G 4G and 5G is great. 2.4G → 5G650) this. width = 650; "alt =" "src =" http://www.bkjia.com/uploads/allimg/131227/01414023B-10.png "/> 650) this. width = 650;" alt = "" src =" http://www.bkjia.com/uploads/allimg/131227/014140B26-11.png "/> The 2G and 4G bandwidths of BNS are interconnected with the Dell E6400 DWA160 5g bandwidths, with an average of 38 M. Because both clients are wireless, the total bandwidth of shared uploading and downloading is based on the features of wireless, the test result is only half of that of wireless → wired, which is normal. As a matter of fact, there are too many wireless networks in the office area, which is very weak .) Summary 802.11n has limited bandwidth in a certain range due to its technology. There are many 2G 4G devices, and most of them use the 2G technology for most wireless mouse. In a certain range, the more devices, the better. Many devices share bandwidth. There will also be interference between the device and the device. The intuitive manifestation is that interference will cause a decrease in the data transmission rate. In this test, there is only one 5G device, which can be directly visible within a short distance.) The wireless transmission speed is far more than MB of wired network cards. In the case of low interference, the limit of GB can be exceeded. Due to the characteristics of 5g, the transmission speed is high, but the penetration is poor, it determines the performance of the wall penetration is weak. 5G signal strength is weaker than 2.4G at the same position. However, when the connection is normal, the transmission speed is higher than 2.4 GB.
In this test, due to the large number of 2.4G wireless routers in and around the company, the interference is high. The M wireless route transmission peak of 2.4G should be around M, however, the actual test is less than 70 M. 5G NICs are found to have compatibility problems during the test. The supported BNS in some frequencies are not supported by DWA160, and those supported by DWA160 are not. There is another serious problem. When using 5g to connect to EA4500, the Network may fail to be connected after a network disconnection. In the end, only the route is restarted. In general, the dual-band Wireless AP/route is quite meaningful. Most of Apple's existing devices can match it perfectly, and its transmission speed is much higher than that of 2.4G. Note that you must test the compatibility of the network card and check whether the 5g running status is stable in advance. Because dual-band wireless network card USB) prices are not friendly, we do not recommend that you separately purchase a USB wireless network card. When there are many users using 5G, we recommend that you use 5g routers/AP in one step. Most enterprise-level APS now support dual-band and are worth buying. In short, 5g under 802.11n does not bring a qualitative leap to the network, but it is always better than it is. In the case of hardware matching, there are not many obstacles in the office area, the 5g speed is really different. End this article with the Windows 7 Ad. "It's really different !"
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