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

Version: 2.6

 

 

fragments each of size equal to fragment threshold. By tuning the fragment threshold value, we can get varying fragment sizes. The determination of an efficient fragment threshold is an important issue in this scheme. If the fragment threshold is small, the overlap part of the master and parallel transmissions is large. This means the spatial reuse ratio of parallel transmissions is high. In contrast, with a large fragment threshold, the overlap is small and the spatial reuse ratio is low. However high fragment threshold leads to low fragment overhead. Hence there is a trade-off between spatial re-use and fragment overhead.

Fragment threshold is the maximum packet size used for fragmentation. Packets larger than the size programmed in this field will be fragmented.

If you find that your corrupted packets or asymmetric packet reception (all send packets, for example). You may want to try lowering your fragmentation threshold. This will cause packets to be broken into smaller fragments. These small fragments, if corrupted, can be resent faster than a larger fragment. Fragmentation increases overhead, so you'll want to keep this value as close to the maximum value as possible.

4.11 What is RTS (Request To Send) Threshold?

The RTS threshold is the packet size at which packet transmission is governed by the RTS/CTS transaction. The IEEE 802.11-1997 standard allows for short packets to be transmitted without RTS/CTS transactions. Each station can have a different RTS threshold. RTS/CTS is used when the data packet size exceeds the defined RTS threshold. With the CSMA/CA transmission mechanism, the transmitting station sends out an RTS packet to the receiving station, and waits for the receiving station to send back a CTS (Clear to Send) packet before sending the actual packet data.

This setting is useful for networks with many clients. With many clients, and a high network load, there will be many more collisions. By lowering the RTS threshold, there may be fewer collisions, and performance should improve. Basically, with a faster RTS threshold, the system can recover from problems faster. RTS packets consume valuable bandwidth, however, so setting this value too low will limit performance.

4.12 What is Beacon Interval?

In addition to data frames that carry information from higher layers, 802.11 includes management and control frames that support data transfer. The beacon frame, which is a type of management frame, provides the "heartbeat" of a wireless LAN, enabling

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X-Micro Tech IEEE 802.11b user manual What is RTS Request To Send Threshold?, What is Beacon Interval?
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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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