Pocket Access Point ASUS WL-330g
It seems that the desire for miniaturization and “besprovodizatsii” anything and everything will soon result in the creation of tiny devices so that they can be easily embedded not only in laptops and PDAs, but also in the pens, pencils, and teaspoons.
So, ASUS has introduced a new model of its access point, and, concurrently, a wireless network adapter WL-330g, working in a standard 802.11g. Earlier, the company has already released a similar device that worked in the good old 802.11b, but progress does not stand still and ASUS made the next step, therefore, ahead of competitors by creating a miniature model that supports 54g. By the way, at the recent Computex 2004 was presented quite a lot of potential competitors WL-330g, but it only samples, not the serial device, so what about the real competition is too early.
In our last article about wireless networking equipment company Eimax we are a little acquainted with the terminology and technologies used in wireless networks 802.11. Today we take a closer look at an 802.11g network and technology that they use.
The 802.11g standard is the youngest of the family of 802.11. It was approved about a year ago, in June 2003. As you would expect anything new, 802.11g combines the advantages of its predecessors: 11a and 11b. From the 802.11a technology has been taken orthogonal frequency division multiplexing (OFDM), which allowed to reach the same speed 54 Mbit / s. Of course, the standard allows the connection to a low speed, using a different method of modulation with a strong enough signal. Note that the maximum speed is only possible at the minimum distance. From the 802.11b standard was used frequency band – 2.4 GHz. It was also decided to ensure compatibility with older hardware 802.11b equipment 11g. Therefore, 802.11g can be considered a descendant of 802.11b, which has only improved performance. But this increase was not so easy to achieve, as we just noted, had to change the signal modulation scheme, borrowing it from 11a. For compatibility with 11b had to implement support for the old modulation scheme 802.11b, for example, encoding a complement source (Complementary Code Keying, CCK). As for power, there is also remained as a parent – a 10-100mW.
It is important to note that the changes were much broader: it was necessary to implement a new physical layer for controlling media access 802.11 MAC, which is known as an extension of the physical layer (Extended Rate PHY, ERP).
We think that many will want to know when the modulation which uses the standard. For the mandatory and optional speed supported by OFDM (6, 12, 18, 24, 36, 48 and 54 Mbit / s). For slower connections by 11b-CCK (for 11 and 5.5 Mbit / s) and encoding Barker (2 and 1 Mbit / s).
In that case, if your network running multiple access points, wireless clients can move between them, while maintaining a connection to the network. Each access point creates its own VMBO or basic service area (Basic Service Set – BSS). The client can communicate using a specific access point only if it is in its service area. If the coverage of access points overlap, the customer can switch from one access point to another. If data is being transferred, and the client device and moves from one access point to another, the connection is not broken.
Several access points connected to a single network Ethernet, forming an extended area service (Extended Service Set – ESS). For all members of the same ESS ID assigned to a – SSID or ESSID. Customers must have the same SSID, access point, and that otherwise they would not be able to move from one access point to another without breaking the connection.
In the case of WL-330g is important to note several points about roaming:
guaranteed only roaming between access points of the same type
a client device must also be given the appropriate SSID,
If encryption is used, then the method should be identical for all devices
coverage overlap to avoid gaps of compounds
access points that use the same channel should be located as far as possible away from each other to reduce interference.
ASUS WL-330g is a compact and easy to install an access point and Wireless LAN 802.11g standard one. The access point allows wireless connection at speeds up to 54 Mbit / s, using the modulation used in 11g, as well as in 11b. Thus, it not only allows you to work with the equipment 11g, but is backward compatible with existing networks 11b. Recall that both standards operate in the 2.4GHz band, which, though very heavily loaded, even in our country, but does not require licensing. On the other hand – machines 11a operates in a less busy 5 GHz band, but its use in our country is not allowed.
The device comes in a small colorful box with a transparent window, which is visible WL-330g. So, to see and appreciate the look can before printing package
His new size resembles a pack of cigarettes, the only thing that is slightly shorter. On the upper side are logos, and three LEDs: Ethernet-connection, wireless connection (Wireless) and power (Power). All LEDs have a bright blue color and the brightness is strong enough, so clearly visible even in bright light in the dark, they all seem too bright. The downside is also quite interesting – it can detect the operating mode switch, with which you can choose either AP mode, or mode of the adapter, a loop for fastening the device to the wall, vents, and various stickers. Connectors for Ethernet, power and reset button are on the side of the device. Unfortunately, the device is not able to automatically detect the MDI / MDI-X, but it comes with a small Ethernet-cable you can connect it directly to the Ethernet-adapter to the computer. It is also worth noting that the device can be powered not only by a special adapter supplied, but also from USB, for which comes complete with a special adapter. In addition to already be listed in this unit you can see the paper version for quick installation of the device, CD-ROM with documentation and software, as well as the folder that includes sections for most 330g, its power supply and other accessories.
The model is based on wireless solutions Marvell Libertas 802.11g Access Point. In general, the chipset is quite interesting and allows to achieve excellent results, but more on that later, under performance testing. Note that the device has no external antenna, as well as external connectors for its connections, but the built-in antenna with virtually no issues covering the stated distance. In fairness, we note that the board is still present a miniature connector for antenna connection, but apparently it is not intended to be used. Built-in antenna, made of flat metal spring-loaded plate, located inside. Antennas are connected to the circuit board pads, and disassembly of the body, they remain in one part, and the board – in the other.
Access Point Mode
In this mode, the device operates as an access point, allowing wireless clients to access resources of other clients that are both wired and wireless networks.
In this mode, the device operates as a full Ethernet-adapter, allowing you to access the network from a computer to which it is connected. Here we can distinguish two submode: Infrastructure and Ad-Hoc.
Ad-Hoc mode does not require access points and wireless devices can establish connections with each other directly.
In Infrastructure mode wireless network in the central device is present – an access point through which all connections. It should be noted that the connection to the computer via the interface is Ethernet, you have a computer to which you decide to connect an adapter must be equipped with a network card.
The device supports the following security standards: WEP (Wired Equivalent Privacy) with a key length of 64 and 128 bits, there is support for WPA-PSK (only-TKIP). Of course, I would like to support and meet other standards that can significantly extend the range of possible applications of the device, such as bridge and repeater modes WDS, the lack of which seems even more strange considering that the previous model supported him.