USER’S MANUAL OF X-MICRO WLAN 11b BROADBAND ROUTER

Version: 2.6

 

 

stations to establish and maintain communications in an orderly fashion.

Beacon Interval represents the amount of time between beacon transmissions. Before a station enters power save mode, the station needs the beacon interval to know when to wake up to receive the beacon (and learn whether there are buffered frames at the access point).

4.13 What is Preamble Type?

There are two preamble types defined in IEEE 802.11 specification. A long preamble basically gives the decoder more time to process the preamble. All 802.11 devices support a long preamble. The short preamble is designed to improve efficiency (for example, for VoIP systems). The difference between the two is in the Synchronization field. The long preamble is 128 bits, and the short is 56 bits.

4.14 What is SSID Broadcast?

Broadcast of SSID is done in access points by the beacon. This announces your access point (including various bits of information about it) to the wireless world around it. By disabling that feature, the SSID configured in the client must match the SSID of the access point.

Some wireless devices don't work properly if SSID isn't broadcast (for example the D-link DWL-120 USB 802.11b adapter). Generally if your client hardware supports operation with SSID disabled, it's not a bad idea to run that way to enhance network security. However it's no replacement for WEP, MAC filtering or other protections.

4.15 What is Wi-Fi Protected Access (WPA)?

Wi-Fi’s original security mechanism, Wired Equivalent Privacy (WEP), has been viewed as insufficient for securing confidential business communications. A longer-term solution, the IEEE 802.11i standard, is under development. However, since the IEEE 802.11i standard is not expected to be published until the end of 2003, several members of the WI-Fi Alliance teamed up with members of the IEEE 802.11i task group to develop a significant near-term enhancement to Wi-Fi security. Together, this team developed Wi-Fi Protected Access.

To upgrade a WLAN network to support WPA, Access Points will require a WPA software upgrade. Clients will require a software upgrade for the network interface card, and possibly a software update for the operating system. For enterprise networks, an

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X-Micro Tech IEEE 802.11b user manual What is Preamble Type?, What is Ssid Broadcast?, What is Wi-Fi Protected Access WPA?
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IEEE 802.11b specifications

X-Micro Tech's IEEE 802.11b standard represents a significant advancement in wireless networking technology, forming part of the IEEE 802.11 family designated for wireless local area networks (WLAN). Introduced in the late 1990s, the 802.11b standard was a precursor to modern wireless technologies, bringing considerable improvements in speed, range, and reliability.

One of the main features of IEEE 802.11b is its data transmission capability, achieving speeds of up to 11 Mbps. While this may seem modest by today's standards, it was a groundbreaking advancement that allowed users to access the internet and share files wirelessly at previously unattainable speeds. Additionally, 802.11b supports lower data rates—5.5 Mbps and 2 Mbps—which enhance reliability and range, allowing devices further from the access point to maintain connections.

The technology operates in the 2.4 GHz frequency band, a characteristic that facilitates better penetration through walls and physical barriers. However, this frequency band is also shared with other appliances, such as microwaves and Bluetooth devices, which can lead to interference. Despite this, the standard incorporates a robust form of modulation, specifically complementary code keying (CCK), which enhances its resilience against such interference.

Another significant aspect of IEEE 802.11b is its capacity for extended range. Under optimal conditions, devices can communicate over distances of up to 300 feet indoors and up to 1,000 feet outdoors. This extended range was particularly useful in homes and offices, promoting seamless integration of devices into networks without the cumbersome wiring typically associated with traditional networking.

Security has always been a critical concern in wireless communications. IEEE 802.11b introduced Wired Equivalent Privacy (WEP) for basic data protection. However, limitations in WEP led to the development of more secure protocols such as WPA and WPA2 in later iterations of wireless standards.

In summary, X-Micro Tech's IEEE 802.11b standard laid the groundwork for modern wireless networking. Its key features, such as a maximum data rate of 11 Mbps, compatibility with the 2.4 GHz frequency band, and extended range capabilities, revolutionized network access in homes and businesses. Even as technology has evolved, the impact of 802.11b can still be felt, serving as a building block for subsequent wireless advancements, making it a significant milestone in the history of networking technology.
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