cambridge.next generation wireless lans.802.11n and 802.11ac

Cambridge公司是一家领先的无线局域网技术公司，致力于下一代的无线局域网（WLAN）技术发展。他们的重点研究方向主要包括802.11n和802.11ac两种新一代无线局域网标准。

802.11n是在传统的802.11a/b/g标准基础上进一步发展的一种无线局域网标准。它用于提高无线传输速度和覆盖范围，并减少信号干扰。802.11n采用了多载波传输技术(MIMO)，通过同时使用多个天线和数据流，使数据传输速率大大提高。此外，它还增加了通道绑定和聚集机制，进一步提高了无线网络的性能。

而802.11ac是在前一代标准基础上的进一步创新。它采用了更高的频率范围和更宽的信道带宽，为用户提供了更高速的无线传输体验。802.11ac通过增加多个天线和更好的编码机制，进一步提高了无线网络的传输速率，使得用户可以更快地下载和上传数据。此外，它还采用了增强的空间复用技术，可在高密度网络环境下保持更稳定的连接。

Cambridge公司在研究和开发方面投入了大量资源，致力于优化这两种技术的性能和可靠性。他们通过改进调制解调器、天线设计和信号处理算法等关键要素，来提高数据传输速度和信号强度。此外，他们还通过与其他无线设备的兼容性测试，确保这些新技术可以无缝集成到现有的无线网络中。

综上所述，Cambridge公司在下一代无线局域网技术方面的研究和创新，使得802.11n和802.11ac等标准成为实现更快速和可靠的无线通信的重要推动力。这些技术的进步将进一步提升用户的体验，并推动无线网络的发展。

相关问题

next gerenation wireless lans

### 回答1：
下一代无线局域网（Next Generation Wireless LANs）是指目前正在研制中的下一代无线网络技术。与现有的Wi-Fi技术相比，下一代无线局域网将具有更高的带宽、更低的延迟和更广泛的覆盖范围，从而提供更可靠的无线连接和更快的数据传输速度。

目前，下一代无线局域网技术主要分为两种，分别是IEEE 802.11ax和5G无线技术。IEEE 802.11ax是Wi-Fi 6的技术标准，它可以在2.4GHz和5GHz频段实现更高的数据传输速率和更低的延迟，同时支持更多的设备连接。5G无线技术则是一种全新的无线通信技术，可以在更高频段内提供更高的带宽和更低的延迟，从而实现更快的数据传输速度和更稳定的连接。

下一代无线局域网的应用场景非常广泛，可以用于智能家居、智能城市、物联网、虚拟现实、增强现实等多个领域。例如，下一代无线局域网可以实现高清视频的无线传输、实时交互式游戏、智能家庭设备的互联互通、无线智能医疗设备的监测和控制等。

总之，下一代无线局域网技术的发展将进一步推动无线通信、智能化和物联网的发展，为人们的生活和工作带来更多的便捷和创新。

### 回答2：
随着我们日常使用无线网络的需求越来越高，下一代无线局域网（Next Generation Wireless LANs）已经成为未来无线行业的重要研究领域。这个新一代网络将通过更快的速度、更高的吞吐量和更稳定的性能来提升网络的性能，提供更高效的数据传输和更好的用户体验。

Next Generation Wireless LANs将采用低延迟、高速率、高可靠性和高容量的技术，例如802.11ax和802.11ay等。这些技术将提供更大的网络带宽，可以让更多的设备连接到网络并获得更快的响应速度。

此外，Next Generation Wireless LANs还将包括更智能的安全保护措施，例如网络访问控制、数据加密和身份验证等。这些安全措施将确保网络数据的安全性和完整性，在保护用户和组织的隐私和敏感信息的同时，确保网络的可用性和稳定性。

总的来说，Next Generation Wireless LANs将是一种高速、高效、智能和安全的无线网络技术。它将对数据传输和网络连接速度的提升，以及对用户体验和数据安全的保护等方面都有积极的影响。随着这项技术的不断发展和应用，我们相信它将极大地改善和改变我们的日常生活和工作方式。

Discuss the Ethernet and its two types in detail with a diagram. Classic Ethernet Physical Layer, Classic Ethernet MAC Sublayer Protocol, CSMA/CD with Binary Exponential Backoff, Switched Ethernet

Ethernet is a widely used networking technology that is used for connecting devices in a local area network (LAN). It was first developed by Xerox Corporation in the 1970s and has since become a standard technology used for LANs worldwide. Ethernet uses a bus topology, where all devices share the same communication medium.

There are two main types of Ethernet: Classic Ethernet and Switched Ethernet.

Classic Ethernet:

The Classic Ethernet is the original Ethernet technology that was developed in the 1970s. It is also known as the "thicknet" or "thinnet" Ethernet. The Classic Ethernet uses coaxial cables as the communication medium. In the Classic Ethernet, data is transmitted using baseband signaling.

The Classic Ethernet has two main layers: the Physical layer and the MAC sublayer protocol.

1. Classic Ethernet Physical Layer:

The Classic Ethernet Physical Layer is responsible for transmitting data over the communication medium. It uses coaxial cables as the communication medium. There are two types of coaxial cables used in Classic Ethernet: Thicknet and Thinnet.

a) Thicknet:

Thicknet is a thick coaxial cable that is 0.4 inches in diameter. It is also known as 10Base5 because it supports a maximum data rate of 10 Mbps and can transmit data up to a distance of 500 meters. Thicknet uses a transceiver to transmit and receive data.

b) Thinnet:

Thinnet is a thin coaxial cable that is 0.2 inches in diameter. It is also known as 10Base2 because it supports a maximum data rate of 10 Mbps and can transmit data up to a distance of 185 meters. Thinnet uses a BNC connector to connect devices to the network.

2. Classic Ethernet MAC Sublayer Protocol:

The Classic Ethernet MAC (Media Access Control) Sublayer Protocol is responsible for controlling access to the communication medium. It uses the CSMA/CD (Carrier Sense Multiple Access with Collision Detection) protocol to avoid collisions between data frames.

a) CSMA/CD with Binary Exponential Backoff:

CSMA/CD is a protocol used by Classic Ethernet to avoid collisions between data frames. It works by sensing the communication medium to check if it is free before transmitting data. If the medium is busy, the device waits for a random amount of time before trying again. If a collision occurs, the devices involved in the collision wait for a random amount of time before retransmitting data. The amount of time the device waits before retransmitting data increases exponentially with each collision, which is known as Binary Exponential Backoff.

Switched Ethernet:

The Switched Ethernet is a newer Ethernet technology that was developed in the 1990s. It uses switches instead of hubs to connect devices to the network. In the Switched Ethernet, data is transmitted using broadband signaling.

The Switched Ethernet has two main layers: the Physical Layer and the MAC Sublayer Protocol.

1. Switched Ethernet Physical Layer:

The Switched Ethernet Physical Layer is responsible for transmitting data over the communication medium. It uses twisted-pair cables or fiber optic cables as the communication medium. The most common type of twisted-pair cable used in Switched Ethernet is the 100Base-TX, which supports a maximum data rate of 100 Mbps and can transmit data up to a distance of 100 meters.

2. Switched Ethernet MAC Sublayer Protocol:

The Switched Ethernet MAC Sublayer Protocol is responsible for controlling access to the communication medium. It uses the same CSMA/CD protocol as Classic Ethernet but is rarely used since collisions are avoided by using switches instead of hubs.

Diagram:

Here is a diagram showing the differences between Classic Ethernet and Switched Ethernet:

                       Classic Ethernet                         Switched Ethernet
Communication Medium   Coaxial cables                           Twisted-pair or fiber optic cables
Data Transmission      Baseband signaling                       Broadband signaling
Maximum Data Rate      10 Mbps                                  100 Mbps or higher
Distance                Up to 500 meters (Thicknet)              Up to 100 meters (100Base-TX)
Access Control         CSMA/CD with Binary Exponential Backoff  CSMA/CD or Switches

In conclusion, Ethernet is a widely used networking technology that is used for connecting devices in a local area network (LAN). There are two main types of Ethernet: Classic Ethernet and Switched Ethernet. Classic Ethernet uses coaxial cables as the communication medium and has a maximum data rate of 10 Mbps while Switched Ethernet uses twisted-pair or fiber optic cables and has a maximum data rate of 100 Mbps or higher. Both Classic Ethernet and Switched Ethernet use the CSMA/CD protocol to avoid collisions between data frames.